What is 8/7 of 15?

How to calculate 8/7 of 15?

1. Multiply the whole number by the numerator of the fraction: 15 × 8 = 120
2. Divide this result by denominator of the fraction: 120/7 = 17.142857142857

Since 120/7 is an improper fraction, the result could also be expressed as a mixed number: 17 1/7

How does it work?

The principle behind finding a fraction of a number, such as 8/7 of 15, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{8}{7}=\frac{x}{15}$ (where x represents 8/7 of 15)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $8\times 15=7x$
2. Which gives: $120=7x$
3. Divide both sides by 7 to isolate x: $\frac{120}{7}=\frac{7x}{7}$
4. Which gives the result: $\frac{120}{7}=x$

Thus, 8/7 of 15 is equal to 120/7 (or 17.142857142857 in its decimal form).