What is 1/7 of 87?

How to calculate 1/7 of 87?

1. Multiply the whole number by the numerator of the fraction: 87 × 1 = 87
2. Divide this result by denominator of the fraction: 87/7 = 12.428571428571

Since 87/7 is an improper fraction, the result could also be expressed as a mixed number: 12 3/7

How does it work?

The principle behind finding a fraction of a number, such as 1/7 of 87, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{1}{7}=\frac{x}{87}$ (where x represents 1/7 of 87)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $1\times 87=7x$
2. Which gives: $87=7x$
3. Divide both sides by 7 to isolate x: $\frac{87}{7}=\frac{7x}{7}$
4. Which gives the result: $\frac{87}{7}=x$

Thus, 1/7 of 87 is equal to 87/7 (or 12.428571428571 in its decimal form).