What is 5/1 of 84?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 5/1 of 84? We'll show you a straightforward method to achieve that.

How to calculate 5/1 of 84?

  1. Multiply the whole number by the numerator of the fraction: 84 × 5 = 420
  2. Divide this result by denominator of the fraction: 420/1 = 420

How does it work?

The principle behind finding a fraction of a number, such as 5/1 of 84, is rooted in the method of cross-multiplication.

Consider the following proportion: 5 1 = x 84 (where x represents 5/1 of 84)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 5 × 84 = 1 x
  2. Which gives: 420 = 1 x
  3. Divide both sides by 1 to isolate x: 420 1 = 1 x 1
  4. Which gives the result: 420 1 = x

Thus, 5/1 of 84 is equal to 420/1 (or 420 in its decimal form).