In the last video tutorial, we considered solving percentage problems using proportions. Then, according to the condition of the problem, we needed to find the value of one or another quantity.
This time, the initial and final values are already given to us. Therefore, in tasks it will be required to find percentages. More precisely, by what percentage has this or that value changed. Let's try.
Task. Sneakers cost 3200 rubles. After the price increase, they began to cost 4000 rubles. By what percentage was the price of the sneakers increased?
So, we solve through proportion. The first step - the original price was equal to 3200 rubles. Therefore, 3200 rubles is 100%.
In addition, we were given the final price - 4000 rubles. This is an unknown percentage, so let's denote it as x . We get the following construction:
3200 — 100%
4000 - x%
Well, the condition of the problem is written down. We make a proportion:
The fraction on the left is perfectly reduced by 100: 3200: 100 = 32; 4000: 100 = 40. In addition, you can reduce by 4: 32: 4 = 8; 40: 4 = 10. We get the following proportion:
Let's use the basic property of proportion: the product of the extreme terms is equal to the product of the middle ones. We get:
8 x = 100 10;
8x = 1000.
It's common linear equation. From here we find x :
x=1000:8=125
So, we got the final percentage x = 125. But is the number 125 the solution to the problem? No way! Because the task requires you to find out by what percentage the price of sneakers was increased.
By how many percent - this means that we need to find a change:
∆ = 125 − 100 = 25
We got 25% - that's how much the original price was raised. This is the answer: 25.
Problem B2 for interest #2
Let's move on to the second task.
Task. The shirt cost 1800 rubles. After the price reduction, it began to cost 1530 rubles. By what percentage was the price of the shirt reduced?
We translate the condition into mathematical language. The initial price of 1800 rubles is 100%. And the final price is 1530 rubles - we know it, but it is not known how many percent it is of the original value. Therefore, we denote it by x. We get the following construction:
1800 — 100%
1530 - x%
Based on the resulting record, we make up the proportion:
Let's separate both parts to simplify further calculations. given equation by 100. In other words, the numerator of the left and right fraction we'll cross out two zeros. We get:
Now let's use the basic property of proportion again: the product of the extreme terms is equal to the product of the average ones.
18 x = 1530 1;
18x = 1530.
It remains to find x :
x = 1530: 18 = (765 2) : (9 2) = 765: 9 = (720 + 45) : 9 = 720: 9 + 45: 9 = 80 + 5 = 85
We got that x = 85. But, as in the previous problem, this number in itself is not the answer. Let's go back to our condition. We now know that the new price after the cut is 85% of the old price. And in order to find the changes, you need from the old price, i.e. 100%, subtract new price, i.e. 85%. We get:
∆ = 100 − 85 = 15
This number will be the answer: Please note: exactly 15, and in no case 85. That's all! Problem solved.
Attentive students will probably ask: why in the first task, when finding the difference, we subtracted the initial number from the final number, and in the second task we did exactly the opposite: from the initial 100% we subtracted the final 85%?
Let's clear this up. Formally, in mathematics, the change in value is always the difference between the final value and the initial one. In other words, in the second problem, we should have got not 15, but -15.
However, in no case should this minus be included in the answer, because it has already been taken into account in the condition of the original problem. It says right there about the price reduction. A 15% price decrease is the same as a -15% price increase. That is why in the solution and answer of the problem it is enough to write just 15 - without any minuses.
All, I hope, with this moment we have understood. This concludes our lesson for today. See you soon!
Proportion translated from Latin(proportio) means ratio, evenness of parts, that is, the equality of two relations. The ability to calculate proportions is often necessary in everyday situations.
Sponsored by the placement of P&G Articles on the topic "How to calculate the proportion" How to add square roots How to find the diagonal of a square How to find the coordinates of the vertex of a parabola
A simple example where knowledge about solving proportions needs to be applied is how to calculate 13% of your wages- the very interest that goes to the Pension Fund.
Write two lines of proportion. In the first, indicate the total amount of the salary, which is 100%, that is, for example, 15,000 (rubles) \u003d 100%.
In the line below, indicate the amount to be calculated with the sign "X", which is equal to 13%, that is, X \u003d 13%.
The main property of a proportion is as follows: the product of the extreme terms of the proportion is equal to the product of its middle terms. This means that if you multiply 15,000 by 13, then the resulting number will be equal to the value of X times 100. That is, multiplying the terms of the proportion crosswise, you will get the same value.
To calculate what X is in the end, multiply 15,000 by 13 and divide by 100. You will get 13 percent of your salary is 1950 rubles, so you get 15,000 - 1950 \u003d 13,050 rubles net salaries.
If you need to take 100 grams of powdered sugar for a pie, and you know that 140 grams fit in one faceted glass, make the following proportion:
Calculate what X is.
X \u003d 100 x 1 / 140 \u003d 0.7
That is, you will need 0.7 cups of powdered sugar.
It happens that you need to calculate an integer, knowing only percentage. For example, you know that 21 people in the enterprise, which is 5% of the total number of employees, have an average special education. Set up a proportion to calculate total employees: X (people) = 100%, 21 = 5%. 21 x 100 / 5 = 420 people.
Thus, having written the available data in two lines, the value of the unknown member must be found as follows: multiply among themselves those members of the proportion that are near and above the unknown and divide the resulting number by the value that is diagonally from the unknown.
A \u003d B x C / D; B \u003d A x D / C; C \u003d A x D / B; D \u003d C x B / A
There are several types of diagonals in geometry. A diagonal is a segment that connects two non-adjacent (not belonging to the same side or one edge) vertices of a polygon or polyhedron. There are also diagonals of faces considered as polygons and spatial
The cube is special case a parallelepiped in which each of the faces is formed regular polygon- square. The cube has six sides in total. Calculating the area is not difficult. Sponsored by the placement of P&G Articles on the topic "How to calculate the area of a cube" How to add
What is a proportion? With mathematical point of view, proportion is the equality of two ratios. All parts of the proportion are interdependent, and their result is unchanged. You will need - Algebra Textbook for Grade 7. Sponsored by P&G Placement Related Articles "How to Calculate a Ratio" How to
Often in life you have to use simple mathematical operations quickly and without the help of electronic computers. For example, when calculating wages, thirteen percent must be deducted from the total amount of money. How to do it? After all, subtract different types numbers are impossible, without a definite
Everything is relative. The ratio of some quantities to each other can be expressed as a percentage. For example, by calculating what percentage of liquid from the bulk is contained in 1 kg of tomatoes and cucumbers, you will find out what will be juicier. You will need 1) Paper 2) Pen 3) Calculator Placement Sponsor
Average - important concept used in many branches of mathematics and its applications: statistics, probability theory, economics, etc. The arithmetic mean can be defined as general concept medium size. P&G Placement Sponsor Related Articles "How to Calculate the Average
The ability to decide proportions can be useful in Everyday life. Let's say you have a vinegar essence in your kitchen that contains 40% vinegar, and you need 6% vinegar. There is no way to do without compiling a proportion. You will need a pen, a piece of paper, analytical thinking P&G Placement Sponsor Articles on
From the need for complex mathematical calculations in ordinary person around head goes. Try to figure out how much income tax from your salary. In this case, a simple action will help you - drawing up a proportion. Proportion is the equality of two quotients. It is written in the form
In mathematics, a proportion is the equality of two ratios. All its parts are characterized by interdependence and invariable result. It is enough to consider one example to understand the principle of solving proportions. Sponsored by P&G Placement Related Articles "How to Find a Ratio" How to Subtract a Percentage from an Amount How
From the first grade, kids learn in mathematics lessons such concepts as equality, the signs "greater than" and "less than". Over the years, tasks become more and more difficult, but the requirement to make an equality is also found in them quite often, since the “equal” sign is the basis of any transformations in mathematics.
How to make a proportion? Any student and adult will understand
For solving most problems in mathematics high school knowledge of proportions is required. This simple skill will help not only to perform complex exercises from the textbook, but also delve into the very essence mathematical science. How to make a proportion? Now let's figure it out.
by the most simple example is a problem where three parameters are known, and the fourth must be found. The proportions are, of course, different, but often you need to find some number by percentage. For example, the boy had ten apples in total. He gave the fourth part to his mother. How many apples does the boy have left? This is the simplest example that will allow you to make a proportion. The main thing is to do it. There were originally ten apples. Let it be 100%. This we marked all his apples. He gave one-fourth. 1/4=25/100. So, he has left: 100% (it was originally) - 25% (he gave) = 75%. This figure shows percentage the amount of remaining fruit to the amount available at first. Now we have three numbers by which we can already solve the proportion. 10 apples - 100%, X apples - 75%, where x is the desired amount of fruit. How to make a proportion? It is necessary to understand what it is. Mathematically it looks like this. The equal sign is for your understanding.
It turns out that 10/x = 100%/75. This is the main property of proportions. After all, the more x, the more percent is this number from the original. We solve this proportion and get that x=7.5 apples. Why the boy decided to give a non-integer amount, we do not know. Now you know how to make a proportion. The main thing is to find two ratios, one of which contains the desired unknown.
The solution to the proportion often comes down to simple multiplication and then to division. Children are not taught in schools why this is so. While it is important to understand that proportional relationships are mathematical classics, the very essence of science. To solve proportions, you need to be able to handle fractions. For example, it is often necessary to convert interest to common fractions. That is, a record of 95% will not work. And if you immediately write 95/100, then you can make solid reductions without starting the main count. It’s worth saying right away that if your proportion turned out with two unknowns, then it cannot be solved. No professor can help you here. And your task, most likely, has more complex algorithm correct actions.
Consider another example where there are no percentages. The motorist bought 5 liters of gasoline for 150 rubles. He thought about how much he would pay for 30 liters of fuel. To solve this problem, we denote by x the required amount of money. You can solve this problem yourself and then check the answer. If you have not yet figured out how to make a proportion, then look. 5 liters of gasoline is 150 rubles. As in the first example, let's write 5l - 150r. Now let's find the third number. Of course, it's 30 liters. Agree that a pair of 30 l - x rubles is appropriate in this situation. Let's move on to mathematical language.
5 liters - 150 rubles;
30 liters - x rubles;
We solve this proportion:
That's what we decided. In your task, do not forget to check the adequacy of the answer. It happens that when wrong decision cars reach unrealistic speeds of 5000 kilometers per hour and so on. Now you know how to make a proportion. Also you can solve it. As you can see, there is nothing complicated in this.
How to find the percentage of a number
To find a percentage of a number, for example, 35% of 1000 rubles, you need the same Where did the number 100 come from? From the very definition. A percentage is a hundredth of a number.
On the calculator, you can multiply 1000 by 35 and press the% button
How to find 100 percent
For example, we know that 350 rubles is 35%. How much will be 100%?
Percentage between two numbers
What part is one number of another. For example, how many percent was the plan fulfilled if the income was expected to be 800 rubles, but in the end they received 1040 rubles.
Online interest calculator
It is not necessary to take 100% into account. For example, attendance from Yandex, Google, VKontakte, etc. is 100%. 800 visitors come to the site from Yandex, which is 67% of total number. And with Google - 55 visitors. What percentage of visitors come from Google?
How to calculate by what percentage one number is less than another
The salary went down from 1040 rubles to 800 rubles. By what percent did the salary decrease? How many percent is 800 less than 1040? Unknown 800.
How to find out by what percentage one number is greater than another
The salary increased from 800 to 1040 rubles. By what percent did the salary increase? How many percent is 1040 greater than 800? Unknown 1040.
We write the proportion, we can derive the formula
Increase the number by the specified percentage
The number b is greater than 800 by 30%. We need to calculate the number b.
We write the proportion, we can derive the formula
Example: the amount without VAT is 1000 rubles. How much will the total amount with VAT 18%
Decrease a number by a given percentage
The number a is less than 1040 by 23%. What is a equal to?
We write the proportion, we can derive the formula
Script for web developers
JavaScript is very simple (highlighted mathematical operations in the form tag): input - a field where we enter values
output - the area with the result
parseFloat(g3.value) or g3.valueAsNumber - convert string to number
235 comments:
Nothing is needed (there is a calculator in the phone), but sometimes it may happen that you have to make a script for calculating the cost of a stretch ceiling. NMitra But what about the bank interest, say, on a loan or a deposit? Or the percentage of conversions from the search? Or taxes for IP?
Total: 20% Anonymous I need 20% propolis tincture. I bought a tincture in a pharmacy, but in the instructions and on the bottle there is an inscription: tincture - 1:10 == How to make 20%? NMitra I'm not going to give you advice. I do not have medical education. Anonymous Since school, I can’t stand everything related to numbers, calculations. And oddly enough, I’m studying to be a financier, and the most elementary arithmetic operations I don't know. And when I hear the word "tasks", I feel uncomfortable. NMitra:)) Anonymous ONS ONS ONS ONS! Anonymous is still not clear. or I'm stupid or. I don’t know: (A (bear) *** xD *** I can’t solve the problem: ((Anonymous 1:10 is part of the adult dose for children. If there are 25 ml in the bottle, then multiply 1 ml - this is 25 drops - 25 * 25 (if diluted) continue to calculate percentages, and so many factors depend on how many drops per ml (thickness condition, pipette size, etc.) Anonymous Hello, how can I find out the difference between two numbers in %. how much one number is greater than the second.
e.g. 950000 from 87000
take more for 100%? then the figure turns out to be 91.58, this turns out to be 8.42%. Do I think right? Thank you Anonymous Pancake did not correctly write 95000 and 87000 NMitra Although, no, I did not understand the question correctly.
NMitra It's nice to hear that your work is appreciated, please Nasiba What if the percentage amount is known but the percentage itself is not. For example 3000 principal amount 1400 what percentage of this amount is? NMitra 3000 - 100%
NMitra Happens. An anonymous Contributor contributed 3,500 rubles at 15% per annum, what amount will he receive in 3 years? NMitra Interest accrued or calculated? If they are included, then in what period (every three months, once every six months)?
525*3=1575 (for three) Anonymous I take a loan for 5,000,000 rubles at 20% for 12 months, how much should I pay per month? Write the calculation please. Thank you. NMitra Annual or monthly interest?
* on the payment of interest,
* write-off of the main debt.
* annuity payment in which the amount monthly payments the same (in your case, about 463,172.53 rubles),
* differentiated payment in which the same amount of principal is written off (in your case, 5,000,000 / 12 = 416,666.67):
365 - number of days in a year
Interest: 5,000,000 * 0.2 * 30 / 365 = 82,191.78
Payment: 416,666.67 + 82,191.78 = 498,858.45
Interest: 4,583,333.33 * 0.2 * 31 / 365 = 77,853.88
Payment: 416,666.67 + 77,853.88 = 494,520.55
Interest: 5,000,000 * 0.2 = 1,000,000
Payment: 416,666.67 + 1,000,000 = 1,416,666.67
Balance: 5,000,000 - 416,666.67 = 4,583,333.33
Interest: 4,583,333.33 * 0.2 = 916,666.66
Payment: 416,666.67 + 916,666.66 = 1,333,333.33
Balance: 4,583,333.33 - 416,666.67 = 4,166,666.66
Thanks a lot! Anonymous, please tell me. How to subtract a percentage of the proceeds. By what formula? NMitra Revenue 1000 rubles, percentage to be deducted 35%
1000 * 0.35 \u003d 350 rubles (this is a percentage of revenue, see the first form)
1000 - 350 \u003d 650 rubles (650 rubles remained in revenue) Anonymous Air humidity 97%. Decrease by 1%. What is the air humidity after this? NMitra 96% as far as I understand. Anonymous amount3395 out of this 0.33% per day NMitra 3395*0.33=11.2035 Anonymous instead of 1600 1200 remained by how many percent did NMitra decrease Proportion:
C \u003d 2.2 * B \u003d 2.2 * A / 0.44 \u003d 5
x% is 1000
x = 100000/4600 = 21.73913 (the one who gave 1000€)
21.73913 is x
x \u003d 14500 * 21.73913 / 100 \u003d 3152.17 (the one who gave 1000 €)
3600*100:9900=37% but it's a percentage of 1000
100%-37%=63% is a percentage of 3600
your amount=63% (that's 6237 euros) + invested 3600=9837
mine = 37% (this is 3663 euros) + 1000 = 4663 euros. Anonymous How to prove to them .. that they are wrong .. it turns out their amount increased by 4.5 times .. although total amount-in three with a ponytail. I don't want to fight over money. NMitra You subtract the initial capital from the final amount. Suppose.
And she (see comment 64):
21.73913% (who gave 1000€)
78.26087% (who gave 3600€)
1000 out of 4600 is 1/4.6 of the total (4600/4.6=1000).
1/4 is 25%, 1/4.6 is (100/4.6=21.73913%)
In theory, you need to solve through the proportion 7 * 100 / 0, you cannot divide by 0. This baffles me! NMitra I agree with you, the question is not posed correctly, you can’t divide by zero, you can only infinitely small function. Anonymous So how does the example solve? Seems like a simple problem elementary school, but blew the minds of all my friends, who are around thirty))) NMitra The question would make sense if it sounded like this: "How much right hand does he have more apples than the one on the left?"
7 - 0 = 7 Answer: 7 apples. Maybe a typo? Anonymous Okay. I tell it like it is. My husband at work monitors violations. There were none in the first quarter. In the second, 7 is fixed. The data must be submitted in the form percentage: by what percentage in the second quarter there are more violations. If it were 4 and 5, respectively, then it is not difficult to decide.
NMitra Nothing works, infinity ((
in the second 7 violations, which corresponds to x
or 1000 * 1.12 = 1120
91 years - 20129.03 thousand rubles
92 - 39686.42 thousand rubles
absolute change - 19557.39 thousand rubles
NMitra What were you looking for? Even by eye it can be seen that 20 is less than 40 by half (50%), namely
x=19557.39*100/39686.42=49.28 Anonymous How the sum is calculated if: 1000*1.2^12=8916. NMitra ^ is the degree symbol https://en.wikipedia.org/wiki/%C2%EE%E7%E2%E5%E4%E5%ED%E8%E5_%E2_%F1%F2%E5%EF%E5 %ED%FC#.D0.97.D0.BD.D0.B0.D1.87.D0.BE.D0.BA_.D1.81.D1.82.D0.B5.D0.BF.D0.B5. D0.BD.D0.B8
8,916100448 * 1000 = 8916,100448
In the first case, we will have 1000*1.2^3=1728 on the deposit, i.e. almost 73% growth in three months.
What will happen to the second deposit, but here is the same formula: 1000 * 1.2 ^ 12 = 8916 rubles.
We get almost 800% profit or an increase in the deposit by almost 9 times in one year.
Specifically, this formula interests me, how it works in general or how the percentage of profit grows.
That is, interest is added to total amount. Anonymous Hello,
Thank you for a great site and for calculating percentages. Only I couldn't find "reverse calculation" here. For example, there is a number: 1045, from which I want to take 600 (for further action). Question: these 600, how many percent of 1045? And where is that magic calculator on which it can be calculated? 1045/100=10.45 is one percent. Then 10.45* by 600 ? It turns out nonsense! =6270. What's this? What is this bullshit?
Thank you. NMitra Anonymous,
x = 100000*5/100 = 5000 Anonymous Hello NMitra.
Please tell me how the cost price of 4.3 million rubles was calculated, otherwise nothing converges with me:
turnover is 6 million rubles per month, the average markup is 39%, therefore the cost of production is 4.3 million.
NMitra 4.3 + 4.3 * 39 / 100 = 6
Cost price \u003d O / (1 + N / 100) \u003d 6 / (1 + 39 / 100)
I thought that the margin is considered in this way:
Is that wrong? Then what could I calculate in this way? NMitra 6*39/100 is 39 percent of 6
6 - 2.34 is 61 percent of 6
Anonymous Yes, I had to subtract 39% of the markup from the turnover in order to get the cost price without the markup.
Thanks a lot again! Anonymous Please explain how much less if in 2013 they exported 2800 goods, and in 2014 they exported 2400 goods, always take 2014 for 100%.
14.3% less exported in 2014? NMitra I also get it. Anonymous Thank you Anonymous And in case of an increase, if the amounts are the same, then it will be the same - 14.3% NMitra No, the figure will be different Anonymous Why? NMitra To understand, formulate a problem and offer its solution. Without examples it is more difficult to explain, otherwise you yourself will now understand what the difference is. Anonymous Please tell me how to calculate interest according to the French and German interest system,
if the loan issue date is April 22, 2014, and the repayment date is September 16, the loan rate is 16% per annum.
S = s * (1 + P/100 * d/D)
Interest rate (P) = 16
Number of days in a year (D) = 365 days or 366 ( leap year) days
Number of days (d) = 8 April + 31 May + 30 June + 31 July + 31 August + 16 September = 147 days
Number of days in a year (D) = 360 days
Number of days (d) = 8 April + 30 May + 30 June + 30 July + 30 August + 16 September = 144 days Anonymous NMitra! Thank you, rescued. Anonymous Hello! help calculate interest on a loan
We want to take a loan from the bank, they give 440.000 / payment 11.722 per month for 60 months
NMitra Hello, is the payment constant throughout the entire term or does it decrease with a decrease in the principal debt? Interest monthly or annual? I would focus not on the percentage (a certain number, for example 20%), but on the final amount that you will give to the bank in addition to the principal debt with all additional commissions, including one-time:
703320 - 440000 = 263320 (of which percent)
263320/5 = 52664 (percentage per year)
Anonymous Hello! 40,000 at 9.20% how much interest will be charged in a month? NMitra 40000*0.092=3680
But! Your interest is most likely annual, so you will receive this amount after a year.
And this amount is per month. But not exactly, since usually it is not the number of months that is considered, but the number of days during which the deposit lies. AT different months different amount days.
IF I CORRECTLY THINK IT IS: 344 * 100/30984 = 1.11 NMitra You think right. Anonymous medical care in 2013 there were 121681 appeals, in 2014-118480
Based on the data, how to find the percentage decrease in the number of calls?
the correct solution would be 121681-118480=3201*100/121681= NMitra 121681 - 100%
x \u003d 118480 * 100 / 121681 \u003d 97.37%
Anonymous 65651651 Anonymous help
in 2001, revenue increased by 2 percent compared to 2000, although it was planned to be 2 times by how many percent NMitra's plan was not completed 2 times - this is 200%
200% - 2% \u003d 198% (198% underfulfilled plan) Anonymous help
in the 2nd half of the year, parts were produced by 0.5% compared to the first half of the year, the production plan was not completed by 16.5% by how much% were planned to change the production of a decrease or increase Anonymous help answer the question. A watermelon contains 99% moisture, but after drying (put in the sun for several days), its moisture content is 98%, WHAT % WILL THE WEIGHT OF THE WATERMELO CHANGES AFTER DRYING? many thanks NMitra About production: the problem is formulated incorrectly
"in the 2nd half of the year, parts were produced by 0.5% compared to the first half of the year" - more or less?
x = 40% Anonymous bursts my goal, but in reality he cannot lose half the weight. This means that the mathematical calculation does not coincide with reality. In the summer I will conduct an experiment with watermelon:)))))) Thanks NMitra The ratio of humidity and weight can go on a hyperbole (see graphs elementary functions) Sergey Ryskin Help solve the problem, from which number 20% was taken away to get 600
Sergey Ryskin Using the selection method, I realized that this is 750, do I need it to count in exsel? for this you need a formula, the question is in the formula, how it is written
NMitra 20% = 20/100 = 0.2
total amount: 12901.00 or
Explain to me if possible. NMitra The total amount is incorrectly calculated :)
And if 11740.4 is multiplied by 130% what do we get? NMitra Formulate the questions correctly:
Okay, I still don't get it.
(Example: There is a price list - three columns of prices
wholesale - (1006.00), retail + 35% to wholesale (1358.00), Internet + 25% to wholesale (1258.00).
There is a retail price - 16772.00
we want to give a discount -30% of the amount
Why can not be divided by 130% NMitra 1006 (wholesale)
1006 + 352.1 = 1358.1 (rez 35%)
1358,1 * 0,35 = 475.335
1358,1 - 475,335 = 882,765
Wholesale \u003d Retail / (1 + percent / 100) \u003d 1358.1 / (1 + 35/100) \u003d 1358.1 / 1.35 \u003d 1006
х = 50*100/1100 = 4.55% (percentage of discount from retail in terms of wholesale) Anonymous Thank you so much! russYliusha Hello guys. really need help. Let's say my friend took a bank loan of 15,000 € for five years (60 months), he pays 270 € per month for five years, as a result, it comes out 16,200 €, Question:
How to find out interest rate bank, that is, how much interest the bank takes.
THANK. NMitra 16200 - 15000 = 1200 (for 5 years)
1200 / 5 = 240 (per year)
x% \u003d 240 * 100 / 15000 \u003d 1.6% (annual rate)
15000 / 60 = 250 (principal debt per month)
Could you tell me the formula in excel! Or how to calculate all this in excel!! Thank you very much!! NMitra I have no more knowledge than was given at school in my time. Substitute known
How do you guys know how much I get paid per hour?
Worked 80 hours and received 1000 €,
Thanks in advance!! NMitra 1-x
x = 1000 / 80 = 12.5 € (per hour) maksimovgenya Good day.
4 of them are damaged books.
x = 100 * 4/113 = 3.54% Anonymous Need to find the percentage of 500,000 from 32,000,000, thank you in advance Anonymous There are 2,500 euros on the account, which were deposited for 3 months at 4%. After 3 months, 2570 euros appeared on the account. Am I right in thinking that 4% of 2500 is 100 euros, i.e. the final amount at the end of the term must be 2600 euros. But the operator said that so "stupidly" interest can not be calculated. How is the calculation done in this case? NMitra 32,000,000 - 100%
x = 500,000 * 100 / 32,000,000 = 50 / 32 = 1.5625% (one and a half percent) NMitra Comment 158: Interest is calculated the same in all cases. The operator is obliged to explain to you exactly how the calculation takes place (how many days, what commissions are taken, etc.)!
I am missing the information you provided:
1) as a rule, the percentage is indicated per annum (this way the percentage looks more impressive), but do you have it for three months at once?
2) has it been a full three months since the opening of the account?
3) the bank does not charge one-time commissions when opening/closing an account?
The term "margin" has different meaning, ask your colleagues in the workshop what exactly they mean. NMitra Margin in % - the ratio of the difference between price and cost to price = (Price - Cost) * 100 / Price
Total cost = 900
x - 600 = 400 / 100 * 600 = 2400
x = 2400 + 600 = 3000
0.5 cu. cameras ___ X ?? watt
1.0 cu. cameras ___ 2948 watt NMitra 0.5 is half, but there is some other pattern in the task, not percentages
2552,18 + 382.827 = 2935
z1- final value range
x \u003d (37-22) * 100 / (63-22) \u003d 1500 / 41 \u003d 37%
2 3 4 5 6 7 8 9 10 11 12 Evgeniya Nikolskaya Help me please) 15% was added to the purchase price and the sale price was obtained. How many percent to subtract from the sale price to get the purchase price. NMitra See comment 95
NMitra 500 * 0.05 = 25 Anonymous, please tell me the total transport cost 3700 brought two goods on the same car costing one product 2200 and the second 27800 how to calculate their transport cost NMitra total 2200+27800=30000 (this is 100%)
x \u003d 2200 * 3700 / 30000 \u003d 271
x = 27800*3700/30000 = 3429 Anonymous NMitra
But what about the bank interest, say, on a loan or a deposit? Or the percentage of conversions from the search? Or taxes for IP?
x = (568 - 1.2y)/0.8 = 710 - 1.5y
y = 650 - 710 + 1.5y = -60 + 1.5y
x = 42*23/94 = 10 Artur Nechipuruk Oh, you have already unsubscribed.
Fortunately, the head has not yet become as stupid as not to solve it on its own, I remembered, took out a notebook and independently deduced the proportion needed here .. (you need to practice at least occasionally)
NMitra Multiply the number by 10101 :) Artur Nechipuruk I figured it out yesterday, read the explanations :) Anonymous was 165 became 230 by what % did the volume of sales increase? NMitra 230-165=65
x \u003d 65 * 100 / 165 \u003d 39 (by 39%) Anonymous Question there were cars in the parking lot and trucks cars more by 1.15 times by what percentage of cars more than trucks
Interest Calculator: 7 Basic Interest Operations
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One percent is a hundredth of a number. This concept is used when it is necessary to indicate the ratio of a share to a whole. In addition, several values can be compared as percentages, while necessarily indicating which integer the percentages are calculated relative to. For example, expenses are 10% higher than income or the price of train tickets has increased by 15% compared to the fares of the previous year. A percentage above 100 means that the proportion is greater than the whole, as is often the case in statistical calculations.
Interest as a financial concept - payment, the borrower to the lender for the provision of money for temporary use. In business, there is an expression "to work for interest." AT this case it is understood that the amount of remuneration depends on profit or turnover (commission). It is impossible to do without calculating interest in accounting, business, banking. To simplify the calculations, an online percentage calculator has been developed.
The calculator allows you to calculate:
- Percentage of the set value.
- Percentage of the amount (tax on actual salary).
- Percentage of the difference (VAT from the amount with VAT).
When solving problems on a percentage calculator, you need to operate with three values, one of which is unknown (according to given parameters variable is calculated). The calculation scenario should be selected based on the specified conditions.
Calculation examples
1. Calculate the percentage of a number
To find a number that is 25% of 1,000 rubles, you need:
To calculate on a regular calculator, you need to multiply 1,000 by 25 and press the% button.
2. Definition of an integer (100%)
We know that 250 rubles. is 25% of some number. How to calculate it?
Let's make a simple proportion:
3. Percentage between two numbers
Suppose a profit of 800 rubles was supposed, but they received 1,040 rubles. What is the overage percentage?
The proportion will be:
Overfulfillment of the plan for profit - 30%, that is, implementation - 130%.
4. Calculation not from 100%
For example, a store with three departments is visited by 100% of customers. In the grocery department - 800 people (67%), in the department of household chemicals - 55. What percentage of buyers come to the department of household chemicals?
5. What percentage is one number less than another
The price of the goods fell from 2,000 to 1,200 rubles. By what percent did the commodity become cheaper, or by what percentage is 1,200 less than 2,000?
- 2 000 - 100 %
- 1 200 – Y%
- Y = 1200 × 100 / 2000 = 60% (60% to 1200 of 2000)
- 100% − 60% = 40% (number 1200 is 40% less than 2000)
6. By what percentage is one number greater than another
Salary increased from 5,000 to 7,500 rubles. By what percent did the salary increase? How many percent is 7,500 more than 5,000?
- 5 000 rub. - 100 %
- 7 500 rub. - Y%
- Y = 7,500 × 100 / 5,000 = 150% (in the figure 7,500 is 150% of 5,000)
- 150% - 100% = 50% (the number 7,500 is 50% greater than 5,000)
7. Increase the number by a certain percentage
The price of goods S is higher than 1,000 rubles. by 27%. What is the price of the item?
The online calculator makes calculations much easier: you need to select the type of calculation, enter a number and a percentage (in the case of calculating a percentage, the second number), indicate the accuracy of the calculation, and give a command to start actions.
How to calculate (calculate) the percentage of the amount?
How to calculate the percentage of the amount , you need to know in many cases (when calculating the state duty, credit, etc.). We'll tell how to calculate percentage of a sum using a calculator, proportions and known ratios.
How to find out the percentage of the amount in the general case?
After that, there are two options:
- If you need to find out what percentage is another amount from the original, you just need to divide it by the amount of 1% received earlier.
- If you need the size of the amount, which is, say, 27.5% of the original, you need to multiply the size of 1% by the required percentage.
How to calculate a percentage from an amount using a proportion?
But you can do it differently. To do this, you will have to use knowledge about the method of proportions, which take place within the framework of school course mathematics. It will look like this.
Let us have A - the main amount equal to 100%, and B - the amount, the ratio of which to A as a percentage we need to know. Write down the proportion:
(X in this case is the number of percent).
According to the rules for calculating proportions, we get the following formula:
If you need to find out how much the amount B will be with the already known number of percent of the amount A, the formula will look different:
Now it remains to substitute in the formula known numbers and you can do the calculation.
How to calculate the percentage of the amount using known ratios?
Finally, you can use more in a simple way. To do this, it is enough to remember that 1% in the form decimal fraction is 0.01. Accordingly, 20% is 0.2; 48% - 0.48; 37.5% is 0.375, etc. It is enough to multiply original amount by the corresponding number - and the result will mean the size of the percentage.
In addition, sometimes you can use simple fractions. For example, 10% is 0.1, that is, 1/10, therefore, finding out how much 10% will be is simple: you just need to divide the original amount by 10.
Other examples of such relationships would be:
- 12.5% - 1/8, that is, you need to divide by 8;
- 20% - 1/5, that is, you need to divide by 5;
- 25% - 1/4, that is, divide by 4;
- 50% - 1/2, that is, you need to divide in half;
- 75% is 3/4, that is, you need to divide by 4 and multiply by 3.
True, not all simple fractions useful for calculating interest. For example, 1/3 is close in size to 33%, but not exactly equal: 1/3 is 33.(3)% (that is, a fraction with infinite triples after the decimal point).
How to subtract a percentage from an amount without the help of a calculator
If it is required to subtract from an already known amount unknown number, which is a certain percentage, you can use the following methods:
- Calculate an unknown number using one of the above methods, and then subtract it from the original.
- Immediately calculate the remaining amount. To do this, subtract from 100% the number of percentages that need to be subtracted, and translate the result obtained from percentages into a number using any of the methods described above.
The second example is more convenient, so let's illustrate it. Let's say you need to find out how much will remain if 16% is subtracted from 4779. The calculation will be like this:
- Subtract from 100 (total percent) 16. We get 84.
- We consider how much it will be 84% of 4779. We get 4014.36.
How to calculate (subtract) the percentage from the amount with a calculator in hand
All of the above calculations are easier to do using a calculator. It can be in the form separate device, and in the form special program on a computer, smartphone or regular mobile phone (even the oldest devices in use today usually have this feature). With their help, the question how to calculate percentage from sum, solved very simply:
- The initial amount is collected.
- The "-" sign is pressed.
- Enter the percentage to be subtracted.
- The "%" sign is pressed.
- The "=" sign is pressed.
As a result, the desired number is displayed on the screen.
How to subtract a percentage from the amount using an online calculator
Finally, now there are enough sites on the network where the online calculator function is implemented. In this case, it is not even necessary to know how to calculate percentage: all user operations are reduced to entering in the windows the right numbers(or moving the sliders to get them), after which the result is immediately displayed on the screen.
This function is especially convenient for those who calculate not just an abstract percentage, but a specific size. tax deduction or the amount of the fee. The fact is that in this case the calculations are more complicated: it is required not only to find the percentages, but also to add the constant part of the amount to them. The online calculator allows you to avoid such additional calculations. The main thing is to choose a site that uses data that complies with the current law.
Today we continue a series of video tutorials on percentage problems from the Unified State Examination in mathematics. In particular, we will analyze two completely real tasks from the Unified State Examination and once again we will see how important it is to carefully read the condition of the problem and interpret it correctly.
So the first task is:
Task. Only 95% and 37,500 graduates of the city solved problem B1 correctly. How many people correctly solved problem B1?
At first glance, it seems that this is some kind of task for the caps. Like:
Task. There were 7 birds on the tree. 3 of them flew away. How many birds have flown?
However, let's do the math. We will solve by the method of proportions. So, we have 37,500 students - this is 100%. And also there is a certain number x of students, which is 95% of the very lucky ones who correctly solved problem B1. We write it down:
37 500 — 100%
X - 95%
You need to make a proportion and find x. We get:
Before us classical proportion, but before using the main property and multiplying it crosswise, I propose to divide both parts of the equation by 100. In other words, we cross out two zeros in the numerator of each fraction. Let's rewrite the resulting equation:
According to the basic property of proportion, the product of the extreme terms is equal to the product of the middle terms. In other words:
x = 375 95
It's pretty big numbers, so you have to multiply them by a column. I remind you that it is strictly forbidden to use a calculator on the exam in mathematics. We get:
x = 35625
Total answer: 35,625. That is how many people out of the original 37,500 solved problem B1 correctly. As you can see, these numbers are pretty close, which makes sense because 95% is also very close to 100%. In general, the first task is solved. Let's move on to the second.
Interest problem #2
Task. Only 80% of the city's 45,000 graduates solved problem B9 correctly. How many people solved problem B9 incorrectly?
We solve in the same way. Initially, there were 45,000 graduates - this is 100%. Then, x graduates must be selected from this number, which should be 80% of the original number. We make a proportion and solve:
45 000 — 100%
x - 80%
Let's reduce one zero in the numerator and denominator of the 2nd fraction. Let's rewrite the resulting construction once more:
The main property of proportion: the product of the extreme terms is equal to the product of the middle ones. We get:
45,000 8 = x 10
This is the simplest linear equation. Let's express the variable x from it:
x = 45,000 8:10
We reduce one zero at 45,000 and at 10, the denominator remains one, so all we need is to find the value of the expression:
x = 4500 8
You can, of course, do the same as last time, and multiply these numbers by a column. But let's not make life difficult for ourselves, and instead of multiplying by a column, we decompose the eight into factors:
x = 4500 2 2 2 = 9000 2 2 = 36,000
And now - the most important thing that I talked about at the very beginning of the lesson. You need to carefully read the condition of the problem!
What do we need to know? How many people solved problem B9 not right. And we just found those people who decided correctly. These turned out to be 80% of original number, i.e. 36,000. This means that in order to get the final answer, our 80% must be subtracted from the original number of students. We get:
45 000 − 36 000 = 9000
The resulting number 9000 is the answer to the problem. In total, in this city, out of 45,000 graduates, 9,000 people solved problem B9 incorrectly. Everything, the task is solved.
To solve most problems in high school mathematics, knowledge of proportioning is required. This simple skill will help you not only perform complex exercises from the textbook, but also delve into the very essence of mathematical science. How to make a proportion? Now let's figure it out.
The simplest example is a problem where three parameters are known, and the fourth must be found. The proportions are, of course, different, but often you need to find some number by percentage. For example, the boy had ten apples in total. He gave the fourth part to his mother. How many apples does the boy have left? This is the simplest example that will allow you to make a proportion. The main thing is to do it. There were originally ten apples. Let it be 100%. This we marked all his apples. He gave one-fourth. 1/4=25/100. So, he has left: 100% (it was originally) - 25% (he gave) = 75%. This figure shows the percentage of the amount of fruit left over the amount of fruit that was available first. Now we have three numbers by which we can already solve the proportion. 10 apples - 100%, X apples - 75%, where x is the desired amount of fruit. How to make a proportion? It is necessary to understand what it is. Mathematically it looks like this. The equal sign is for your understanding.
10 apples = 100%;
x apples = 75%.
It turns out that 10/x = 100%/75. This is the main property of proportions. After all, the more x, the more percent is this number from the original. We solve this proportion and get that x=7.5 apples. Why the boy decided to give a non-integer amount, we do not know. Now you know how to make a proportion. The main thing is to find two ratios, one of which contains the desired unknown.
Solving a proportion often comes down to simple multiplication and then division. Children are not taught in schools why this is so. While it is important to understand that proportional relationships are mathematical classics, the very essence of science. To solve proportions, you need to be able to handle fractions. For example, it is often necessary to convert percentages to ordinary fractions. That is, a record of 95% will not work. And if you immediately write 95/100, then you can make solid reductions without starting the main count. It’s worth saying right away that if your proportion turned out with two unknowns, then it cannot be solved. No professor can help you here. And your task, most likely, has a more complex algorithm for correct actions.
Consider another example where there are no percentages. The motorist bought 5 liters of gasoline for 150 rubles. He thought about how much he would pay for 30 liters of fuel. To solve this problem, we denote by x the required amount of money. You can solve this problem yourself and then check the answer. If you have not yet figured out how to make a proportion, then look. 5 liters of gasoline is 150 rubles. As in the first example, let's write 5l - 150r. Now let's find the third number. Of course, it's 30 liters. Agree that a pair of 30 l - x rubles is appropriate in this situation. Let's move on to mathematical language.
5 liters - 150 rubles;
30 liters - x rubles;
We solve this proportion:
x = 900 rubles.
That's what we decided. In your task, do not forget to check the adequacy of the answer. It happens that with the wrong decision, cars reach unrealistic speeds of 5000 kilometers per hour and so on. Now you know how to make a proportion. Also you can solve it. As you can see, there is nothing complicated in this.
Proportion - equality of two relations, i.e. equality of the form a:b = c:d , or, in other notation, the equality
If a a : b = c : d, then a and d called extreme, a b and c - averagemembers proportions.
There is no getting away from the “proportion”, it is indispensable in many tasks. There is only one way out - to deal with this ratio and use the proportion as a lifesaver.
Before proceeding with the consideration of proportion problems, it is important to remember the basic rule of proportion:
in proportion
the product of the extreme terms is equal to the product of the average
If some value in the proportion is unknown, it will be easy to find it based on this rule.
For example,
I.e unknown quantity proportions - the value of a fraction, in the denominator
which is the number opposite the unknown value
, in the numerator - the product of the remaining members of the proportion
(regardless of where this unknown value stands
). 
Task 1.
From 21 kg of cottonseed, 5.1 kg of oil was obtained. How much oil will be obtained from 7 kg of cottonseed?
Decision:
We understand that a decrease in the weight of a seed by a factor of several times entails a decrease in the weight of the resulting oil by the same amount. That is, the quantities are directly related.
Let's fill in the table: 
Unknown value - the value of the fraction, in the denominator of which - 21 - the value opposite the unknown in the table, in the numerator - the product of the remaining members of the table-proportion.
Therefore, we get that 1.7 kg of oil will come out of 7 kg of seed.
To right fill in the table, it is important to remember the rule:
Identical names must be written under each other. We write percentages under percentages, kilograms under kilograms, etc.
Task 2.
Convert to radians.
Decision:
We know that . Let's fill in the table:
Task 3.
On the checkered paper a circle is shown. What is the area of the circle if the area of the shaded sector is 27?
Decision:
It is clearly seen that the unshaded sector corresponds to the angle at (for example, because the sides of the sector are formed by the bisectors of two adjacent right angles). And since the whole circle is , then the shaded sector accounts for .
Let's make a table:
Where does the area of the circle come from?
Task 4. After 82% of the entire field had been plowed, 9 hectares remained to be plowed. What is the area of the entire field?
Decision:
The whole field is 100%, and since 82% is plowed, then 100%-82%=18% of the field remains to be plowed.
Fill in the table: 
Where do we get that the whole field is (ha).
And the next task is with an ambush.
Task 5.
The distance between two cities is traveled by a passenger train at a speed of 80 km/h in 3 hours. How many hours will it take for a freight train to travel the same distance at a speed of 60 km/h?
If you solve this problem in the same way as the previous one, you will get the following:
the time it takes for a freight train to travel the same distance as a passenger train is hours. That is, it turns out that, going at a lower speed, it overcomes (in the same time) the distance faster than a train with a higher speed.
What is the reasoning error?
So far, we have considered problems where the quantities were directly proportional to each other , i.e growth of the same magnitude by a certain amount, gives growth the second quantity associated with it by the same number of times (similarly with a decrease, of course). And here we have a different situation: the speed of a passenger train more the speed of a freight train by a factor of several times, but the time required to overcome the same distance is required by a passenger train lesser as much as a freight train. That is, values to each other inversely proportional .
The scheme that we have used so far needs to be slightly modified in this case.
Decision:
We reason like this:
A passenger train traveled 3 hours at a speed of 80 km/h, so it traveled km. This means that a freight train will cover the same distance in one hour.
That is, if we were to make up a proportion, we should have swapped the cells of the right column first. Would have received:
So, please be careful when drawing up the proportion. First, figure out what kind of addiction you are dealing with - direct or reverse.
