What is 4/9 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 4/9 of 84? We'll show you a straightforward method to achieve that.

How to calculate 4/9 of 84?

  1. Multiply the whole number by the numerator of the fraction: 84 × 4 = 336
  2. Divide this result by denominator of the fraction: 336/9 = 37.333333333333
  3. Simplify by dividing both the numerator and denominator by their GCD (3):
    • 336/3 = 112
    • 9/3 = 3
  4. Which gives: 112/3

Since 112/3 is an improper fraction, the result could also be expressed as a mixed number: 37 1/3

How does it work?

The principle behind finding a fraction of a number, such as 4/9 of 84, is rooted in the method of cross-multiplication.

Consider the following proportion: 4 9 = x 84 (where x represents 4/9 of 84)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 4 × 84 = 9 x
  2. Which gives: 336 = 9 x
  3. Divide both sides by 9 to isolate x: 336 9 = 9 x 9
  4. Which gives the result: 336 9 = x (or 112 3 = x )

Thus, 4/9 of 84 is equal to 112/3 (or 37.333333333333 in its decimal form).