What is 7/2 of 15?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 7/2 of 15? We'll show you a straightforward method to achieve that.

How to calculate 7/2 of 15?

  1. Multiply the whole number by the numerator of the fraction: 15 × 7 = 105
  2. Divide this result by denominator of the fraction: 105/2 = 52.5

Since 105/2 is an improper fraction, the result could also be expressed as a mixed number: 52 1/2

How does it work?

The principle behind finding a fraction of a number, such as 7/2 of 15, is rooted in the method of cross-multiplication.

Consider the following proportion: 7 2 = x 15 (where x represents 7/2 of 15)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 7 × 15 = 2 x
  2. Which gives: 105 = 2 x
  3. Divide both sides by 2 to isolate x: 105 2 = 2 x 2
  4. Which gives the result: 105 2 = x

Thus, 7/2 of 15 is equal to 105/2 (or 52.5 in its decimal form).