What is 5/10 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 5/10 of 55? We'll show you a straightforward method to achieve that.

How to calculate 5/10 of 55?

  1. Multiply the whole number by the numerator of the fraction: 55 × 5 = 275
  2. Divide this result by denominator of the fraction: 275/10 = 27.5
  3. Simplify by dividing both the numerator and denominator by their GCD (5):
    • 275/5 = 55
    • 10/5 = 2
  4. Which gives: 55/2

Since 55/2 is an improper fraction, the result could also be expressed as a mixed number: 27 1/2

How does it work?

The principle behind finding a fraction of a number, such as 5/10 of 55, is rooted in the method of cross-multiplication.

Consider the following proportion: 5 10 = x 55 (where x represents 5/10 of 55)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 5 × 55 = 10 x
  2. Which gives: 275 = 10 x
  3. Divide both sides by 10 to isolate x: 275 10 = 10 x 10
  4. Which gives the result: 275 10 = x (or 55 2 = x )

Thus, 5/10 of 55 is equal to 55/2 (or 27.5 in its decimal form).