School mathematics. How to find a percentage of the number

The word "percent" in Greek means hundredth part of a number. In mathematics, and throughout the world, it is considered to be absolute for 100%. Based on this principle, all computational rules are constructed.

There are several options for tasks related to the goal of calculating the percentage of the number. Each such task has its own individual solution principle.

Find a percentage of the number

The condition of the problem is given a certain numerical value and you want to find its percentage. For example, we have the number 47 and it is necessary to calculate it 25%.

Decision:To solve, we take the original number as 100%. After that, this percentage is translated into decimal and we get that 25% = 0.25. Multiply 47 by the percentage expressed by fractions, and we get the desired number 47 * 0.25 = 11.75.

Answer: 11.75 is 25% of the number 47.

Find the number by percentage

The next kind of tasks associated withthe question of how to find the percentage of a number is the calculation of the value of the existing percentage. Given that 57 is 45% of a certain number. It is required to find this number.

Decision:To solve this problem, it is necessary to divide the available number by the percentage that it is from the whole. So, we get that 57 / 0.45 = 126.67. To better understand this action, it will be useful to disassemble the whole process in detail. 57 is 45%, i.e. to find the value of one percent, it is necessary to divide the number by the number of percent. It turns out that 1% of the integer is 1.2667. Further, to find the integer, we multiply the resulting value by 100.

Answer: The number, 45% of which is 57, is 126.67.

Find how many percent one number is from another

It’s a little harder to do tasks whereIt is necessary to find the percentage value that one number is from another. How to find the percentage of the number in this case? The answer is very simple. Consider it on a small example. We have two numbers: suppose it is 45 and 58. To find out how many percent is 45 from 58 you need to multiply it by 100 and divide by 58. We get that 45 is 77.6% of 58.

You can often see situations where people do notunderstand how the price of the product will change if it rises by 15%. People forget elementary school math and for this reason they are wondering how to find a percentage of the number.

Knowledge of the percentage message in the field ofexchange communications and operations. When making deposits in a bank account, we also deal with interest. There, the principle of floating interest or capitalization often operates, which slightly complicates the principle of calculating the final result.

As we can see, with a slight repetition, you canease to remember, or re-learn, how to find a percentage of the number, and indeed, how to work with a similar mathematical and financial unit. This knowledge will not only expand the general human horizon, but will also help you to more confidently navigate situations with changes in prices, exchange rates, bank interest rates, profit margins and other very important processes. Of course, at first glance it seems that the ability to calculate in the mind can save only a few seconds, but a minute won from making one decision can result in several days released in a year.