What is 2/4 of 39?

Often, in mathematics or everyday life, we need to find a fraction of a given number. For instance, how would you quickly calculate 2/4 of 39? We'll show you a straightforward method to achieve that.

How to calculate 2/4 of 39?

  1. Multiply the whole number by the numerator of the fraction: 39 × 2 = 78
  2. Divide this result by denominator of the fraction: 78/4 = 19.5
  3. Simplify by dividing both the numerator and denominator by their GCD (2):
    • 78/2 = 39
    • 4/2 = 2
  4. Which gives: 39/2

Since 39/2 is an improper fraction, the result could also be expressed as a mixed number: 19 1/2

How does it work?

The principle behind finding a fraction of a number, such as 2/4 of 39, is rooted in the method of cross-multiplication.

Consider the following proportion: 2 4 = x 39 (where x represents 2/4 of 39)

  1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: 2 × 39 = 4 x
  2. Which gives: 78 = 4 x
  3. Divide both sides by 4 to isolate x: 78 4 = 4 x 4
  4. Which gives the result: 78 4 = x (or 39 2 = x )

Thus, 2/4 of 39 is equal to 39/2 (or 19.5 in its decimal form).