What is 4/10 of 71?

How to calculate 4/10 of 71?

1. Multiply the whole number by the numerator of the fraction: 71 × 4 = 284
2. Divide this result by denominator of the fraction: 284/10 = 28.4
3. Simplify by dividing both the numerator and denominator by their GCD (2):
   • 284/2 = 142
   • 10/2 = 5
4. Which gives: 142/5

Since 142/5 is an improper fraction, the result could also be expressed as a mixed number: 28 2/5

How does it work?

The principle behind finding a fraction of a number, such as 4/10 of 71, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{4}{10}=\frac{x}{71}$ (where x represents 4/10 of 71)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $4\times 71=10x$
2. Which gives: $284=10x$
3. Divide both sides by 10 to isolate x: $\frac{284}{10}=\frac{10x}{10}$
4. Which gives the result: $\frac{284}{10}=x$ (or $\frac{142}{5}=x$)

Thus, 4/10 of 71 is equal to 142/5 (or 28.4 in its decimal form).