What is 10/7 of 87?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 10/7 of 87? We'll show you a straightforward method to achieve that.

How to calculate 10/7 of 87?

  1. Multiply the whole number by the numerator of the fraction: 87 × 10 = 870
  2. Divide this result by denominator of the fraction: 870/7 = 124.28571428571

Since 870/7 is an improper fraction, the result could also be expressed as a mixed number: 124 2/7

How does it work?

The principle behind finding a fraction of a number, such as 10/7 of 87, is rooted in the method of cross-multiplication.

Consider the following proportion: 10 7 = x 87 (where x represents 10/7 of 87)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 10 × 87 = 7 x
  2. Which gives: 870 = 7 x
  3. Divide both sides by 7 to isolate x: 870 7 = 7 x 7
  4. Which gives the result: 870 7 = x

Thus, 10/7 of 87 is equal to 870/7 (or 124.28571428571 in its decimal form).