What is 2/5 of 55?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 2/5 of 55? We'll show you a straightforward method to achieve that.

How to calculate 2/5 of 55?

  1. Multiply the whole number by the numerator of the fraction: 55 × 2 = 110
  2. Divide this result by denominator of the fraction: 110/5 = 22
  3. Simplify by dividing both the numerator and denominator by their GCD (5):
    • 110/5 = 22
    • 5/5 = 1
  4. Which gives: 22/1

How does it work?

The principle behind finding a fraction of a number, such as 2/5 of 55, is rooted in the method of cross-multiplication.

Consider the following proportion: 2 5 = x 55 (where x represents 2/5 of 55)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 2 × 55 = 5 x
  2. Which gives: 110 = 5 x
  3. Divide both sides by 5 to isolate x: 110 5 = 5 x 5
  4. Which gives the result: 110 5 = x (or 22 1 = x )

Thus, 2/5 of 55 is equal to 22/1 (or 22 in its decimal form).