May be useful not only for the student high school. IN everyday life this skill is necessary in order to calculate the loan payment, calculate and check whether the accountants correctly calculated the amount of taxation upon receipt wages. And many employees various companies and for enterprises this skill is simply necessary for work.
What is this - percentage? From the school curriculum, everyone remembers that a percentage in the world is considered to be a hundredth part of something. That is, to put it another way, the expression “3 percent” should be understood as 3 hundredths of any number. For the sake of brevity, people have adopted the symbol "%" for the word "percentage".
And from school, we all know how to calculate the percentage of divided by one hundred, finding the value of one percent, and then the resulting quotient is multiplied by a number indicating the number of percents that need to be found.
For example, you need to find out what 28% of 500 is. The line of reasoning should be as follows:
- Find the size of 1% of 500 by division.
- We find given number multiplying the resulting quotient from division by 100.
That is, 28% of 500 is 28/100 of 500. Another way to write this action is:
500 X 28/100 = 140.
Since numbers are not always easy to remember, and pen and paper are not always at hand, many people today use calculators.
To calculate, you can use the described method: divide the given number by one hundred and multiply by required amount percent.
There is a faster calculation option:
- The specified number is entered into the calculator. In our case - 500.
- Next, press the “multiply” key.
- Then we type the number of the required percentages - for our version it is 28.
- Instead of equality, select the % sign on the calculator.
- We get the result - this is 140 in our example.
- In the cell that displays the calculated percentage, enter the equal sign “=”.
- Next, write down a given number from which you need to look for a percentage, or the “address” of the cell where this number has already been entered. In our example we will enter the number 500.
- The third step is to set the “multiply” or “*” sign.
- Now you should write down the number that reflects the amount of interest you are looking for. For us it's 28.
- The penultimate action will be to enter the “percentage” sign, which looks like “%”.
- To get the result, all you have to do is press the “Enter” button on your keyboard. The result - 140 - will immediately appear on the monitor.
Before starting to work in Excel, you should left-click to set the appropriate format in the table cells or use the “menu” function: “format - cells - number - percentage”.
For example, we are given the numbers 140 and 500. The question is posed this way: what percentage is 140 of 500?
- First, let's find what one percent of 500 is equal to. That is, we follow the old scheme and divide 500 by 100. We get 5.
- Now it remains to find out how many such percentages the given number 140 contains. To do this, 140 must be divided by 5. We get the same 28 percent!
- This calculation can be written in one formula as follows:
140: (500: 100) = 140: 500/100 = 140: 500 X 100 = 28.
That is, the number 140 out of 500 is 28 percent.
And in order to find out what percentage one number is of another, we should divide the smaller number by the larger one and multiply the quotient by 100.
These skills are extremely important for an entrepreneur who is engaged in trading. When setting prices for a product, it usually requires the ability to calculate the percentage of a number, since with the help of this action the necessary “markup” on the product is made. It is most convenient to mark up the entire assortment at the same percentage, for example, 15%.
But calculating net income requires another skill. For example, the daily revenue at the stall was 3,450 rubles. What is the net income from goods sold? Some novice entrepreneurs naively calculate 15% of gross revenue, and make a grave mistake! Having removed the “cheating” obtained in such an incorrect way from circulation, they then sit and puzzle over where the shortage came from.
And everything is very simple. After markup, the product began to contain not 100% of the cost, but 100% + 15% = 115%. Therefore, to find the amount of added value received, 15% is calculated as follows:
- They find 1% of the revenue by dividing it not by 100, but by 115. That is, in our case
- And now you can look for added value, which you can bravely extract from circulation.
These numbers are taken out of thin air, so you should not take these data seriously. But the calculation methods themselves deserve attention; there are no errors in them.
A percentage is one hundredth of a number taken as a whole. Percentages are used to indicate the relationship of a part to the whole, as well as to compare quantities.
1% = 1 100 = 0,01
The interest calculator allows you to perform the following operations:
Find the percentage of a number
To find the percentage p from a number, you need to multiply this number by a fraction p 100
Let's find 12% of the number 300:
300 12
100
= 300 · 0.12 = 36
12% of 300 is 36.
For example, a product costs 500 rubles and there is a 7% discount on it. Let's find the absolute value of the discount:
500 7
100
= 500 · 0.07 = 35
Thus, the discount is 35 rubles.
What percentage is one number of another?
To calculate the percentage of numbers, you need to divide one number by another and multiply by 100%.
Let's calculate what percentage the number 12 is from the number 30:
12
30
· 100 = 0.4 · 100 = 40%
The number 12 is 40% of the number 30.
For example, a book contains 340 pages. Vasya read 200 pages. Let's calculate what percentage of the entire book Vasya read.
200
340
· 100% = 0.59 · 100 = 59%
Thus, Vasya read 59% of the entire book.
Add percentage to number
To add to a number p percent, you need to multiply this number by (1 + p 100)
Add 30% to the number 200:
200 (1 + 30
100
) = 200 1.3 = 260
200 + 30% equals 260.
For example, a swimming pool subscription costs 1000 rubles. Starting next month they promised to raise the price by 20%. Let's calculate how much a subscription will cost.
1000 (1 + 20
100
) = 1000 1.2 = 1200
Thus, the subscription will cost 1200 rubles.
Subtract the percentage from the number
To subtract from a number p percent, you need to multiply this number by (1 - p 100)
Subtract 30% from the number 200:
200 · (1 - 30
100
) = 200 · 0.7 = 140
200 - 30% equals 140.
For example, a bicycle costs 30,000 rubles. The store gave it a 5% discount. Let's calculate how much the bike will cost taking into account the discount.
30000 · (1 - 5
100
) = 30000 0.95 = 28500
Thus, the bike will cost 28,500 rubles.
What percentage is one number greater than another?
To calculate how many percent one number is greater than another, you need to divide the first number by the second, multiply the result by 100 and subtract 100.
Let's calculate what percentage is the number 20 more number 5:
20
5
· 100 - 100 = 4 · 100 - 100 = 400 - 100 = 300%
The number 20 is 300% greater than the number 5.
For example, the boss’s salary is 50,000 rubles, and the employee’s salary is 30,000 rubles. Let's find out how many percent the boss's salary is greater:
50000
35000
· 100 - 100 = 1.43 * 100 - 100 = 143 - 100 = 43%
Thus, the boss's salary is 43% higher than the employee's salary.
What percentage is one number less than another?
To calculate how many percent one number is less than another, you need to subtract from 100 the ratio of the first number to the second, multiplied by 100.
Let's calculate what percentage is the number 5 less number 20:
100 - 5
20
· 100 = 100 - 0.25 · 100 = 100 - 25 = 75%
The number 5 is 75% less than the number 20.
For example, freelancer Oleg completed orders worth 40,000 rubles in January, and 30,000 rubles in February. Let's find how many percent less Oleg earned in February than in January:
100 - 30000
40000
· 100 = 100 - 0.75 * 100 = 100 - 75 = 25%
Thus, in February Oleg earned 25% less than in January.
Find 100 percent
If the number x This p percent, then you can find 100 percent by multiplying the number x on 100p
Let's find 100% if 25% is 7:
7 · 100
25
= 7 4 = 28
If 25% equals 7, then 100% equals 28.
For example, Katya copies photos from her camera to her computer. In 5 minutes, 20% of the photos were copied. Let's find how long the copying process takes:
5 · 100
20
= 5 5 = 25
We find that the process of copying all photos takes 30 minutes.
Good day!
Interest, I tell you, is not only something “boring” in mathematics lessons at school, but also an extremely necessary and practical thing in life (found everywhere: when you take out a loan, open a deposit, calculate profits, etc. ). And in my opinion, when studying the topic of “percentages” in the same school, extremely little time is devoted to this ().
Perhaps because of this, some people find themselves in not very pleasant situations (many of which could have been avoided if they had figured out what was there and how in time...).
Actually, in this article I want to look at the most popular problems with percentages that occur in life (of course, I will consider this as much as possible in simple language with examples). Well, forewarned means forearmed (I think that knowledge of this topic will allow many to save both time and money).
And so, closer to the topic...
Option 1: calculate prime numbers in your head in 2-3 seconds.
In the vast majority of cases in life, you need to quickly estimate in your mind how much a 10% discount on a certain number (for example) will be. Agree, in order to make a purchasing decision, you don’t need to calculate everything down to the penny (it’s important to figure out the order).
The most common variants of numbers with percentages are given in the list below, as well as what you need to divide the number by to find out the desired value.
Simple examples:
- 1% of the number = divide the number by 100 (1% of 200 = 200/100 = 2);
- 10% of a number = divide the number by 10 (10% of 200 = 200/10 = 20);
- 25% of a number = divide the number by 4 or twice by 2 (25% of 200 = 200/4 = 50);
- 33% of the number ≈ divide the number by 3;
- 50% of a number = divide the number by 2.
Problem! For example, you want to buy equipment for 197 thousand rubles. The store offers a 10.99% discount if you meet certain conditions. How can you quickly figure out if it’s worth it?
Example solution. Yes, just round these pair of numbers: instead of 197, take the amount of 200, instead of 10.99%, take 10% (conditionally). In total, you need to divide 200 by 10 - i.e. we estimated the size of the discount at approximately 20 thousand rubles. (with some experience, the calculation is done almost automatically in 2-3 seconds).
Exact calculation: 197 * 10.99/100 = 21.65 thousand rubles.
Option 2: use the Android phone calculator
When you need a more accurate result, you can use a calculator on your phone (in the article below I will give screenshots from Android). It's quite simple to use.
For example, you need to find 30% of the number 900. How to do this?
Yes, quite simple:
- open the calculator;
- write 30%900 (of course, the percentage and number can be different);
- Please note that below your written “equation” you will see the number 270 - this is 30% of 900.
Below are more complex example. We found 17.39% of the number 393,675 (result 68460, 08).
If you need, for example, to subtract 10% from 30,000 and find out how much it will be, then you can write it like this (by the way, 10% of 30,000 is 3000). Thus, if you subtract 3000 from 30,000, you will get 27,000 (which is what the calculator showed).
In general, very handy tool, when you need to calculate 2-3 numbers and get accurate results, down to tenths/hundredths.
Option 3: count the percentage of the number (the essence of the calculation + the golden rule)
It is not always and not everywhere possible to round numbers and calculate percentages in your head. Moreover, sometimes it is necessary not only to obtain some exact result, but also to understand the very “essence of the calculation” (for example, to calculate a hundred/thousand different problems in Excel).
Let's say we need to find 17.39% of the number 393,675. Let's solve this simple problem...
To remove all the points on "Y", I will consider the inverse problem. For example, what percentage is the number 30,000 of the number 393,675.
Option 4: calculate percentages in Excel
Excel is good because it allows you to make fairly voluminous calculations: you can simultaneously calculate dozens of different tables by linking them together. And in general, is it possible to manually calculate percentages for dozens of items of goods, for example.
Below I will show a couple of examples that you most often encounter.
Problem one. There are two numbers, for example, the purchase and sale price. You need to find out the difference between these two numbers as a percentage (how much more/less one is than the other).
For a more precise understanding, I will give one more example. Another problem: there is a purchase price and the desired percentage of profit (let's say 10%). How to find out the selling price. Everything seems to be simple, but many people “stumble”...
Additions on the topic are always welcome...
That's all, good luck!
Every person in his life almost every day encounters the concept of interest. Moreover, this applies not only to obtaining a percentage value from one number, but also to solving the problem of how to calculate a percentage of the sum of numbers. IN Everyday life and in everyday life, many do not pay attention to this, nevertheless, all these calculations have been embedded in us since school.
What is percentage
As for the concept of interest, it can be explained in the most in a simple way, without going into the basics of mathematical calculations yet. A percentage actually represents some part of something else. It does not matter in what indicator the correspondence of the percentage in relation to the main original source will be expressed. The main thing is to understand that such a representation can be in the form of a percentage itself (%) or in the form of a fraction, which ultimately determines the ratio of the percentage to the original version.
Using percentages in practice
Each of us already knows how to calculate interest. school course mathematics. In everyday life, we encounter percentages almost every minute. Any housewife, when preparing a dish, uses a recipe in which the percentage is presented. The simplest example: take half a glass of milk... This is a mathematical interpretation of what a certain part is in relation to the whole.
The basis for absolutely all calculations is considered to be 100 percent (100%) or one (1) if the calculation is made using fractions. This is what is used as a starting point when calculating any component of the initial indicator.
The same applies to the question of how to calculate the percentage of an amount when the initial (100 percent) indicator is not one number, but several. There can be quite a lot of calculation options here. Let's look at the most basic ones.
Calculating percentages by proportion
Now we will not take into account the calculation of percentages using the same tables of office programs such as Excel, which do this automatically when the appropriate formula is specified.
In some cases, a calculator is used on which you can specify the calculation of such actions. But that’s not what we’re talking about now.
Let's consider the most common methods of calculations that are familiar to us from the school mathematics course.
The simplest and most common way is to solve the proportion.
IN in this case the original number is given as 100 percent (say, some arbitrary number “a”), and its part (say, “b”) is given as an unknown “x”. In mathematics it looks like this:
a = 100%;
Based on the rules of proportion, you can calculate the unknown number x. For this, the so-called crossover method is used. In other words, you need to multiply b by 100 and divide by a. Exactly the same rule applies if, in the case of drawing up a proportion, you swap b and x in places, when the percentage is known, but you need to calculate the part in numerical terms.
Quick interest calculation
Of course, calculating percentages using proportions is fundamental. However, with the use fractional numbers This procedure is simplified to the point of impossibility. After all, what is 50% really? Half. That is, 1/2 or 0.5 (based on the starting number 1). Now it’s clear: to calculate half, you need to multiply the desired number either by 1/2, or by 0.5, or divide by 2. This method, however, is only suitable for numbers that are divisible without a remainder.
In case of a remainder or infinite signs in the period after the decimal point like 0.33333333..., it is better to use fractional expressions like 1/3. By the way, it is fractions (in some cases irrational) that accurately reflect the number itself, because periodic numbers after the decimal point, no matter how much you ask, will still not give a whole number. And the same one third clearly and clearly expresses the very essence.
In the same recipes, naturally, a third can be determined, so to speak, by eye. But in chemical processes, especially those involving fine dosages of components, say, in pharmaceuticals, this method will not work. You can't rely on your eyes here. It is necessary to use exact ratios of ingredients, even if one of the indicators is in the form of a number with a figure in the period or is presented in the form of the same irrational fraction. But, as a rule, for example when weighing, such numbers can be limited after the decimal point to ten thousandths or a maximum of hundred thousandths.
How to calculate percentage of amount
Very often you have to deal with several required numbers or their sum. The question of how to calculate the percentage of an amount is solved as simply as in the case of using one starting number. The only thing that needs to be taken into account in this case is the usual presentation of the amount as a single value.
For example, we have two numbers, a and b, and the initial indicator is the number d. In this case, the proportion will look like this:
d = 100%;
(a + b) = x.
Note that the sum (a + b) can still be expressed as a single number. Let it be z. In the case when we set the formula a + b = z, the proportion takes on a completely standard form:
d = 100%;
As you can see, there is nothing complicated about this.
There is another option when the sum (a + b) = 100%, and d = x.
Here the solution looks like this:
(d x 100)/(a + b) or (d/(a + b)) + 100/(a + b).
As is already clear, the principle of a common denominator for fractions is used here.
If you add a and b, the sum of which is equal to z, then the proportion again returns to the standard form:
z = 100%;
The same applies in reverse.
Mathematical explanation
From the point of view of mathematics and its fundamentals, solving the problem of how to calculate a percentage of a sum comes down to only applying the simplest rules for opening parentheses when multiplying a sum by a single number and finding a common denominator, which, in general, is what it is. In other words, it can be represented in formulaic expression like this:
a x (b + c) = ab + ac,
where ab and ac are the products of the terms in brackets (b and c) by the number (coefficient) in front of the brackets a.
Actually, the same method works in proportion. Let's say we have a certain number z, which represents 100%, and the sum of the numbers a and b. The percentage to be calculated will be denoted by the unknown number y. In this version, the proportion takes the form:
z = 100%;
(a + b) = y.
Hence the simple solution:
((a + b) x 100%)/z = ((a x 100%) + (b x 100%))/z
The actions are taken in brackets in order to emphasize that multiplication operations are performed first, and addition of products - second. The same action is performed if the initial sum of the numbers is 100%.
Reverse calculation
Very often, in the question of how to calculate a percentage of an amount, an unambiguous reverse translation arises. In practice, this involves, say, the reverse calculation of a quarter. Everyone knows that this figure is 25% of the initial number. Let, for example, the price of a product be increased by 25%, which amounts to 25 rubles. You need to find out how much this product costs. Now let's try to figure out how to calculate not the initial number, knowing the percentage value, but the entire amount that should be obtained in the end. It would seem that the solution is simple:
25 = 25% (1/4 or 0.25);
x = 100%.
No, absolutely wrong. This way you can only get the original number, without taking into account the 25%. To calculate the entire amount, taking into account 25%, you need to use the formula:
25 = 25%;
x = 100% + 25%.
Or 100/0.8, which is what the value 125 (100 + 25) will show, since 100% plus 25% in the unit expression is the number 1.25 (one plus a quarter), and in reverse view(1/x) is exactly 0.8. Having carried out the calculations, we find that x = 125.
Conclusion
As you can see, there is nothing particularly complicated about how to calculate the percentage of the amount. True, in school curriculum For some reason, the reverse translation is often omitted. Then many accountants working on reports with payment of the same VAT very often have problems.
So you just have to take into account the basic rules for calculating interest, and the problems will disappear by themselves.
On the other hand, for convenience, both proportions and fractions can be used equally. In the first case we have, so to speak, classic version, and in the second - simple and universal solution. Again, it is better to use it in case of division without a remainder. But when calculating the most popular shares such as half, quarter, third, etc., this method is very convenient.
Reverse calculations, as can be seen from the above examples, are also not something complicated. The main thing is to take into account the inverse coefficient when calculating the desired number. I think everything has fallen into place now. As they say, simple mathematics.
How to find the percentage of a number? How to calculate the percentage of the amount?
To find, for example, 5% of the number 123, you need to: multiply 5 by 123 and divide by 100.
How to calculate your body fat percentage?
There are many methods for determining the amount of fat in the human body. For these purposes, there are online diet percentage calculators that calculate Body Mass Index (BMI). To implement this method, which determines the percentage of body fat in a woman or man, body parameters such as height, weight and circumference are needed.
Calculating percentage formula
Interest calculator by deposit. Deposits – favorable storage cash savings. To increase your liquidity and multiply money turnover banks attract legal and individuals so that they put their cash savings in a deposit account. And since at the moment there are a huge number of banks, considerable competition is formed, in which each bank tries to attract customers various methods. Some banking institutions offer higher interest rates, others - monthly payment percent, and still others – the possibility of replenishment. Taking into account these manipulations, deposits can be classified into several types:
- time deposits;
- demand deposits;
- savings deposits.
Time deposits - Deposit interest calculator
A time deposit in a bank means a bank deposit issued for a specified period, for example, 1 year. Having placed savings on such a deposit, the owner will not be able to partially or completely withdraw them from his personal account. Of course, it is possible to close a time deposit, but this will violate the terms of the agreement, which will result in penalties being assessed by the bank. They may consist in not accruing interest on the deposit or in accruing interest at the lowest rate. Also, in some banking institutions, in order to withdraw a deposit early, you must wait a certain period. For example, after writing an application to close a deposit, the client will be able to pick it up only after a week. In most cases, time deposits cannot be replenished either. As for interest rates, in this case they are the maximum.
Demand deposits - interest calculator
Keeping cash savings on demand deposit is advantageous because they can be replenished and withdrawn (in whole or in part) at any time. Sometimes such a deposit is also called a deposit with free use. Banks charge a lower interest rate on it, because in this case they cannot have the entire amount of money invested.
Savings deposits.
Savings deposits are banking services offered by the bank that involve opening a deposit for a set period of time with the possibility of replenishment. Thanks to the possibility of replenishing invested cash savings, the owner personal account will be able to preserve and increase personal funds.
Before investing your savings, you need to carefully familiarize yourself with what banking services banks offer. Calculate the amounts on the deposit interest calculator. And only after that, choosing the most profitable terms, you can open a deposit agreement.
