The calculation of the percentage of the number is one of the fundamental topics that everyone goes to school in mathematics. But this does not mean that everyone masters it with ease. In fact, the topic is simple, the main thing is to know the proven methods of calculating the whole in parts and percent of the whole.
1% is the hundredth part of the whole, so knowing this value, you can easily calculate the value of the part. For example, 15% of the number 60 can be calculated as follows: we take 60 for 100 percent. Then 1% is 60/100 - 0.6. 15%, therefore, will be - 0.6 * 15 = 9. This is the first way to calculate the percentage of the number.
The second way is to make a proportion. 15 refers to 100, as x relates to 60, i.e. 15/100 = x / 60. There are two ways to solve the compiled proportion:
- Convert it to the expression x = 15 * 60/100. And again it turns out: x = 9.
- Make another conversion, in 2 actions: 100x = 15 * 60, that is, numbers in proportions are multiplied crosswise. From this expression we get the following: 100x = 900. Therefore, x = 9.
If you need to find out what percentage of the number is another number, the formula is also very simple. Take the numbers 70 and 13 as an example. Let 70 be 100% and 13 be x. Then 13/70 = x / 100. You can solve this proportion in familiar ways.
70x = 13 * 100; 70x = 1300; If you round to the second decimal place, it turns out that x = 18.57%.
If the percentage of a certain number is known and you need to find this number, then this problem can also be solved.
For example, 16% is 32. What is an integer? Again we make up the proportion: 16% refers to 100%, as well as 32 to x. 16/100 = 32 / x; 16x = 3200; x = 3200/16 = 200.
If the condition of the problem is such that the number A is a certain percentage of the number B, which must be calculated, then another very simple formula is applied. A / B * 100% - this will be the answer. For example, you need to find out how many percent the number 87 is from the number 329.
Calculating the result by the formula, we get 87/329 * 100% = 26.44%. If the formula is forgotten at the right time, the proportions will come to the rescue: 87 refers to 329, as x refers to 100%, that is, 87/329 = x / 100. Transforming this proportion, we get 329x = 87 * 100; 329x = 8700; x = 8700/329 = 26.44%.
Well, the simplest proportions are almost always heard and in my head: one fifth is 20%, one tenth is 10%, half and a quarter are 50% and 25%, respectively. For some it is more convenient and clearer to think in parts, while for someone it is easier to operate with interest. There is no big difference between one second and 50%.
It will be easy and simple with a calculator, because there is even a special button there that allows you to calculate percentages.
Of course, all these tasks are simply a consolidation of the theory. But to calculate the percentage of the number may be needed in life. At sales, to find out if a 30% discount is worth grabbing on a thing or if it is a tiny amount. You can find out what the price was before the discount, as well as double-check the sellers - after all, they often use the carelessness of buyers and indicate extremely attractive numbers on the price tags.
It may be necessary to calculate the percentage of the number when calculating taxes, of course, for those who track such things. And, of course, accountants, economists,
stock brokers and analysts are constantly faced with interest calculation. In fact, even housewives constantly deal with interest, without noticing it themselves.
In a word, the topic is not complicated, although it seems at first glance very difficult. However, when understanding comes, the tasks related to calculating percentages of a number and an integer in part will seem like seeds. You just need to fill your hand and move your brain a little.