What is 4/8 of 91?

How to calculate 4/8 of 91?

1. Multiply the whole number by the numerator of the fraction: 91 × 4 = 364
2. Divide this result by denominator of the fraction: 364/8 = 45.5
3. Simplify by dividing both the numerator and denominator by their GCD (4):
   • 364/4 = 91
   • 8/4 = 2
4. Which gives: 91/2

Since 91/2 is an improper fraction, the result could also be expressed as a mixed number: 45 1/2

How does it work?

The principle behind finding a fraction of a number, such as 4/8 of 91, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{4}{8}=\frac{x}{91}$ (where x represents 4/8 of 91)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $4\times 91=8x$
2. Which gives: $364=8x$
3. Divide both sides by 8 to isolate x: $\frac{364}{8}=\frac{8x}{8}$
4. Which gives the result: $\frac{364}{8}=x$ (or $\frac{91}{2}=x$)

Thus, 4/8 of 91 is equal to 91/2 (or 45.5 in its decimal form).