What is 5/7 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 5/7 of 64? We'll show you a straightforward method to achieve that.

How to calculate 5/7 of 64?

  1. Multiply the whole number by the numerator of the fraction: 64 × 5 = 320
  2. Divide this result by denominator of the fraction: 320/7 = 45.714285714286

Since 320/7 is an improper fraction, the result could also be expressed as a mixed number: 45 5/7

How does it work?

The principle behind finding a fraction of a number, such as 5/7 of 64, is rooted in the method of cross-multiplication.

Consider the following proportion: 5 7 = x 64 (where x represents 5/7 of 64)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 5 × 64 = 7 x
  2. Which gives: 320 = 7 x
  3. Divide both sides by 7 to isolate x: 320 7 = 7 x 7
  4. Which gives the result: 320 7 = x

Thus, 5/7 of 64 is equal to 320/7 (or 45.714285714286 in its decimal form).