# Difference between revisions of "1988 AJHSME Problems/Problem 6"

## Problem

$\frac{(.2)^3}{(.02)^2} =$

$\text{(A)}\ .2 \qquad \text{(B)}\ 2 \qquad \text{(C)}\ 10 \qquad \text{(D)}\ 15 \qquad \text{(E)}\ 20$

## Solution

Converting the decimals to fractions gives us $\frac{(.2)^3}{(.02)^2} =\frac{\left( \frac{1}{5}\right)^3}{\left(\frac{1}{50}\right)^2}=\frac{50^2}{5^3}=\frac{2500}{125}=20\Rightarrow \mathrm{(E)}$.

## Solution 2

We expand $\frac{(0.2)^3}{(0.02)^2}$, and get $\frac{(0.2) \times (0.2) \times (0.2)}{(0.02) \times (0.02)}$. The two $0.02$'s "cancel" out with the two $0.2$'s, leaving the fraction as: $(10) \times (10) \times (0.2)$. Using basic calculations, we compute this expression to get $20\Rightarrow \mathrm{(E)}$.

~sakshamsethi

## See Also

 1988 AJHSME (Problems • Answer Key • Resources) Preceded byProblem 5 Followed byProblem 7 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 All AJHSME/AMC 8 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.

Invalid username
Login to AoPS