What is 10/8 of 85?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 10/8 of 85? We'll show you a straightforward method to achieve that.

How to calculate 10/8 of 85?

  1. Multiply the whole number by the numerator of the fraction: 85 × 10 = 850
  2. Divide this result by denominator of the fraction: 850/8 = 106.25
  3. Simplify by dividing both the numerator and denominator by their GCD (2):
    • 850/2 = 425
    • 8/2 = 4
  4. Which gives: 425/4

Since 425/4 is an improper fraction, the result could also be expressed as a mixed number: 106 1/4

How does it work?

The principle behind finding a fraction of a number, such as 10/8 of 85, is rooted in the method of cross-multiplication.

Consider the following proportion: 10 8 = x 85 (where x represents 10/8 of 85)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 10 × 85 = 8 x
  2. Which gives: 850 = 8 x
  3. Divide both sides by 8 to isolate x: 850 8 = 8 x 8
  4. Which gives the result: 850 8 = x (or 425 4 = x )

Thus, 10/8 of 85 is equal to 425/4 (or 106.25 in its decimal form).