What is 4/7 of 18?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 4/7 of 18? We'll show you a straightforward method to achieve that.

How to calculate 4/7 of 18?

  1. Multiply the whole number by the numerator of the fraction: 18 × 4 = 72
  2. Divide this result by denominator of the fraction: 72/7 = 10.285714285714

Since 72/7 is an improper fraction, the result could also be expressed as a mixed number: 10 2/7

How does it work?

The principle behind finding a fraction of a number, such as 4/7 of 18, is rooted in the method of cross-multiplication.

Consider the following proportion: 4 7 = x 18 (where x represents 4/7 of 18)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 4 × 18 = 7 x
  2. Which gives: 72 = 7 x
  3. Divide both sides by 7 to isolate x: 72 7 = 7 x 7
  4. Which gives the result: 72 7 = x

Thus, 4/7 of 18 is equal to 72/7 (or 10.285714285714 in its decimal form).