What is 9/10 of 58?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 9/10 of 58? We'll show you a straightforward method to achieve that.

How to calculate 9/10 of 58?

  1. Multiply the whole number by the numerator of the fraction: 58 × 9 = 522
  2. Divide this result by denominator of the fraction: 522/10 = 52.2
  3. Simplify by dividing both the numerator and denominator by their GCD (2):
    • 522/2 = 261
    • 10/2 = 5
  4. Which gives: 261/5

Since 261/5 is an improper fraction, the result could also be expressed as a mixed number: 52 1/5

How does it work?

The principle behind finding a fraction of a number, such as 9/10 of 58, is rooted in the method of cross-multiplication.

Consider the following proportion: 9 10 = x 58 (where x represents 9/10 of 58)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 9 × 58 = 10 x
  2. Which gives: 522 = 10 x
  3. Divide both sides by 10 to isolate x: 522 10 = 10 x 10
  4. Which gives the result: 522 10 = x (or 261 5 = x )

Thus, 9/10 of 58 is equal to 261/5 (or 52.2 in its decimal form).