What is 1/10 of 90?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 1/10 of 90? We'll show you a straightforward method to achieve that.

How to calculate 1/10 of 90?

  1. Multiply the whole number by the numerator of the fraction: 90 × 1 = 90
  2. Divide this result by denominator of the fraction: 90/10 = 9
  3. Simplify by dividing both the numerator and denominator by their GCD (10):
    • 90/10 = 9
    • 10/10 = 1
  4. Which gives: 9/1

How does it work?

The principle behind finding a fraction of a number, such as 1/10 of 90, is rooted in the method of cross-multiplication.

Consider the following proportion: 1 10 = x 90 (where x represents 1/10 of 90)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 1 × 90 = 10 x
  2. Which gives: 90 = 10 x
  3. Divide both sides by 10 to isolate x: 90 10 = 10 x 10
  4. Which gives the result: 90 10 = x (or 9 1 = x )

Thus, 1/10 of 90 is equal to 9/1 (or 9 in its decimal form).