What is 2/4 of 31?

How to calculate 2/4 of 31?

1. Multiply the whole number by the numerator of the fraction: 31 × 2 = 62
2. Divide this result by denominator of the fraction: 62/4 = 15.5
3. Simplify by dividing both the numerator and denominator by their GCD (2):
   • 62/2 = 31
   • 4/2 = 2
4. Which gives: 31/2

Since 31/2 is an improper fraction, the result could also be expressed as a mixed number: 15 1/2

How does it work?

The principle behind finding a fraction of a number, such as 2/4 of 31, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{2}{4}=\frac{x}{31}$ (where x represents 2/4 of 31)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $2\times 31=4x$
2. Which gives: $62=4x$
3. Divide both sides by 4 to isolate x: $\frac{62}{4}=\frac{4x}{4}$
4. Which gives the result: $\frac{62}{4}=x$ (or $\frac{31}{2}=x$)

Thus, 2/4 of 31 is equal to 31/2 (or 15.5 in its decimal form).