What is 3/4 of 13?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 3/4 of 13? We'll show you a straightforward method to achieve that.

How to calculate 3/4 of 13?

  1. Multiply the whole number by the numerator of the fraction: 13 × 3 = 39
  2. Divide this result by denominator of the fraction: 39/4 = 9.75

Since 39/4 is an improper fraction, the result could also be expressed as a mixed number: 9 3/4

How does it work?

The principle behind finding a fraction of a number, such as 3/4 of 13, is rooted in the method of cross-multiplication.

Consider the following proportion: 3 4 = x 13 (where x represents 3/4 of 13)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 3 × 13 = 4 x
  2. Which gives: 39 = 4 x
  3. Divide both sides by 4 to isolate x: 39 4 = 4 x 4
  4. Which gives the result: 39 4 = x

Thus, 3/4 of 13 is equal to 39/4 (or 9.75 in its decimal form).