2009 AMC 10A Problems/Problem 7

Problem

A carton contains milk that is $2$ % fat, an amount that is $40$ % less fat than the amount contained in a carton of whole milk. What is the percentage of fat in whole milk?

$\mathrm{(A)}\ \frac{12}{5} \qquad \mathrm{(B)}\ 3 \qquad \mathrm{(C)}\ \frac{10}{3} \qquad \mathrm{(D)}\ 38 \qquad \mathrm{(E)}\ 42$

Solution

Rewording the question, basically, we are being asked " $2$ is $40$ % less than what number?" If $x$ represents the number we are looking for, then $40%$ (Error compiling LaTeX. Unknown error_msg) less than the number would be represented by $x-0.4x$ or $0.6x$ . Thus $0.6x=2$ ; solving for $x$ , we get $x=\frac{10}{3}$ , $\longrightarrow \fbox{C}$

2009 AMC 10A (Problems • Answer Key • Resources)
Preceded by Problem 6	Followed by Problem 8
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 AMC 10 Problems and Solutions

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

Page

Toolbox

Search

2009 AMC 10A Problems/Problem 7

Problem

Solution

See also