If you know the percentage of a number, you can find out the whole number.

For example, a business paid us \$60000 for a job, and that is 2% of the total profit the business made. Knowing our share, and how much percentage it is, we can find out the total profit.

First you need to find out how many dollars is one percent. How to do it? Try to guess by carefully studying the following picture:

If 2 % of the total profit is \$60,000, then it's easy to guess that one percent is \$30,000. And to get that \$30,000, you have to divide \$60,000 by two.

60 000 : 2 = 30 000

We found one percent of the total profit, i.e., . If one part is 30 thousand, then to determine one hundred parts, you must multiply 30 thousand by 100

30 000 Ã— 100 = 3 000 000

We found out the total profit. It is three million.

Let's try to learn a rule for finding a number by its percentage.

To find a number by its percentage, you need to divide the known number by the percentage and multiply the result by 100.

Example 2. The number 35 is 7% of some unknown number. Find this unknown number.

Read the first part of the rule:

To find a number by its percentage, you need to divide the known number by the percentage

We have a known number, 35, and a given percentage, 7. Let's divide 35 by 7

35 : 7 = 5

Read the second part of the rule:

and multiply the result by 100

Our result is number 5. Multiply 5 by 100

5 Ã— 100 = 500

500 is the unknown number you wanted to find. You can do a test. To do this, we find 7% of 500. If we did everything correctly, we should get 35

500 : 100 = 5

5 Ã— 7 = 35

We got 35. So the exercise was solved correctly.

The method of finding a number by its percentage is the same as the usual way of finding a whole number by its fraction. If percentages are confusing and difficult at first, you can replace percentages with a fractional form.

For example, the previous problem can be stated as follows: The number 35 is of some unknown number. Find this unknown number. We already know how to solve such problems. This is finding a number by a fraction. To find a number with a fraction, we divide the number by the numerator of the fraction, and multiply the result by the denominator of the fraction. In this example, we divide the number 35 by 7 and multiply the result by 100.

35 : 7 = 5

5 Ã— 100 = 500

In the future we will be solving exercises based on percentages, some of which will be complicated. In order to learn it easily at first, it is enough to be able to find a percentage of a number, and a number by a percentage.