What is 7/8 of 89?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 7/8 of 89? We'll show you a straightforward method to achieve that.

How to calculate 7/8 of 89?

  1. Multiply the whole number by the numerator of the fraction: 89 × 7 = 623
  2. Divide this result by denominator of the fraction: 623/8 = 77.875

Since 623/8 is an improper fraction, the result could also be expressed as a mixed number: 77 7/8

How does it work?

The principle behind finding a fraction of a number, such as 7/8 of 89, is rooted in the method of cross-multiplication.

Consider the following proportion: 7 8 = x 89 (where x represents 7/8 of 89)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 7 × 89 = 8 x
  2. Which gives: 623 = 8 x
  3. Divide both sides by 8 to isolate x: 623 8 = 8 x 8
  4. Which gives the result: 623 8 = x

Thus, 7/8 of 89 is equal to 623/8 (or 77.875 in its decimal form).