What is 1/7 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 1/7 of 84? We'll show you a straightforward method to achieve that.

How to calculate 1/7 of 84?

  1. Multiply the whole number by the numerator of the fraction: 84 × 1 = 84
  2. Divide this result by denominator of the fraction: 84/7 = 12
  3. Simplify by dividing both the numerator and denominator by their GCD (7):
    • 84/7 = 12
    • 7/7 = 1
  4. Which gives: 12/1

How does it work?

The principle behind finding a fraction of a number, such as 1/7 of 84, is rooted in the method of cross-multiplication.

Consider the following proportion: 1 7 = x 84 (where x represents 1/7 of 84)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 1 × 84 = 7 x
  2. Which gives: 84 = 7 x
  3. Divide both sides by 7 to isolate x: 84 7 = 7 x 7
  4. Which gives the result: 84 7 = x (or 12 1 = x )

Thus, 1/7 of 84 is equal to 12/1 (or 12 in its decimal form).