What is 8/4 of 85?

How to calculate 8/4 of 85?

1. Multiply the whole number by the numerator of the fraction: 85 × 8 = 680
2. Divide this result by denominator of the fraction: 680/4 = 170
3. Simplify by dividing both the numerator and denominator by their GCD (4):
   • 680/4 = 170
   • 4/4 = 1
4. Which gives: 170/1

How does it work?

The principle behind finding a fraction of a number, such as 8/4 of 85, is rooted in the method of cross-multiplication.

Consider the following proportion: $\frac{8}{4}=\frac{x}{85}$ (where x represents 8/4 of 85)

1. Using the cross-multiplication method, multiply both numerators by their opposite denominators: $8\times 85=4x$
2. Which gives: $680=4x$
3. Divide both sides by 4 to isolate x: $\frac{680}{4}=\frac{4x}{4}$
4. Which gives the result: $\frac{680}{4}=x$ (or $\frac{170}{1}=x$)

Thus, 8/4 of 85 is equal to 170/1 (or 170 in its decimal form).