What is 4/8 of 43?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 4/8 of 43? We'll show you a straightforward method to achieve that.

How to calculate 4/8 of 43?

  1. Multiply the whole number by the numerator of the fraction: 43 × 4 = 172
  2. Divide this result by denominator of the fraction: 172/8 = 21.5
  3. Simplify by dividing both the numerator and denominator by their GCD (4):
    • 172/4 = 43
    • 8/4 = 2
  4. Which gives: 43/2

Since 43/2 is an improper fraction, the result could also be expressed as a mixed number: 21 1/2

How does it work?

The principle behind finding a fraction of a number, such as 4/8 of 43, is rooted in the method of cross-multiplication.

Consider the following proportion: 4 8 = x 43 (where x represents 4/8 of 43)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 4 × 43 = 8 x
  2. Which gives: 172 = 8 x
  3. Divide both sides by 8 to isolate x: 172 8 = 8 x 8
  4. Which gives the result: 172 8 = x (or 43 2 = x )

Thus, 4/8 of 43 is equal to 43/2 (or 21.5 in its decimal form).