2012 AMC 8 Problems/Problem 1

Revision as of 10:21, 23 November 2013 by Knittingfrenzy18 (talk | contribs) (Solution)

Problem

Rachelle uses 3 pounds of meat to make 8 hamburgers for her family. How many pounds of meat does she need to make 24 hamburgers for a neighborhood picnic?

$\textbf{(A)}\hspace{.05in}6 \qquad \textbf{(B)}\hspace{.05in}6\dfrac23 \qquad \textbf{(C)}\hspace{.05in}7\dfrac12 \qquad \textbf{(D)}\hspace{.05in}8 \qquad \textbf{(E)}\hspace{.05in}9$

Solution

Solution 1

Since Rachelle uses $3$ pounds of meat to make $8$ hamburgers, she uses $\frac{3}{8}$ pounds of meat to make one hamburger. She'll need 24 times that amount of meat for 24 hamburgers, or $\frac{3}{8} \cdot 24 = \boxed{\textbf{(E)}\ 9}$.

Solution 2

Rachelle uses meat for hamburgers in the ratio $\frac{3\text{ lb}}{8\text{ hamburgers}}$. If we multiply this ratio on top and bottom by 3 to get 24 hamburgers on the bottom, we get $\frac{3\text{ lb}\cdot 3}{8\text{ hamburgers}\cdot 3} = \frac{9\text{ lb}}{24\text{ hamburgers}}$. Therefore, she uses 9 pounds of meat for 24 hamburgers, making the answer $\boxed{\textbf{(E)}\ 9}$.

See Also

2012 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
First Problem
Followed by
Problem 2
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

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