Finding the fraction by number

Fractions are used in mathematics to briefly denote part of the quantity in question.

But if there is a part, then there must be a whole (that’s why this part was taken).

Knowing the whole, one can find its part indicated by the corresponding fraction.

Example. Consider the task.

The book has 160 pages. Yura read 4/5 books. How many pages did Jura read?

First of all, we find an integer in the problem. This is the whole book and there are only 160 pages.

Let's look at the fraction (part) from the whole: 4/5. The denominator is 5, which means that the whole is divided into 5 parts and we can find how many pages it is 1/5 part.

1. 160: 5 = 32 (p.) - makes up 1/5 of the pages.
2. The numerator of a fraction is 4, so 4 parts are taken.
3. 32 • 4 = 128 (p.) - make up 4/5 of the book.

Both actions can be written briefly, in accordance with the rule of finding a part of the whole .

Answer: Yura read 128 pages.