What is 8/5 of 64?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 8/5 of 64? We'll show you a straightforward method to achieve that.

How to calculate 8/5 of 64?

  1. Multiply the whole number by the numerator of the fraction: 64 × 8 = 512
  2. Divide this result by denominator of the fraction: 512/5 = 102.4

Since 512/5 is an improper fraction, the result could also be expressed as a mixed number: 102 2/5

How does it work?

The principle behind finding a fraction of a number, such as 8/5 of 64, is rooted in the method of cross-multiplication.

Consider the following proportion: 8 5 = x 64 (where x represents 8/5 of 64)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 8 × 64 = 5 x
  2. Which gives: 512 = 5 x
  3. Divide both sides by 5 to isolate x: 512 5 = 5 x 5
  4. Which gives the result: 512 5 = x

Thus, 8/5 of 64 is equal to 512/5 (or 102.4 in its decimal form).