Art of Problem Solving
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2013 AMC 8 Problems/Problem 5: Difference between revisions

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==Solution==
==Solution==
The median here is OBVIOUSLY less than the mean, so option (A) and (B) are out.
The median here is obviously less than the mean, so option (A) and (B) are out.


Lining up the numbers (5, 5, 6, 8, 106), we see that the median weight is 6 pounds.
Lining up the numbers (5, 5, 6, 8, 106), we see that the median weight is 6 pounds.

Revision as of 02:38, 6 March 2014

Problem

Hammie is in the $6^\text{th}$ grade and weighs 106 pounds. His quadruplet sisters are tiny babies and weigh 5, 5, 6, and 8 pounds. Which is greater, the average (mean) weight of these five children or the median weight, and by how many pounds?

$\textbf{(A)}\ \text{median, by 60} \qquad \textbf{(B)}\ \text{median, by 20} \qquad \textbf{(C)}\ \text{average, by 5} \qquad \textbf{(D)}\ \text{average, by 15} \qquad \textbf{(E)}\ \text{average, by 20}$

Solution

The median here is obviously less than the mean, so option (A) and (B) are out.

Lining up the numbers (5, 5, 6, 8, 106), we see that the median weight is 6 pounds.

The average weight of the five kids is $\dfrac{5+5+6+8+106}{5} = \dfrac{130}{5} = 26$.

Therefore, the average weight is bigger, by $26-6 = 20$ pounds, making the answer $\boxed{\textbf{(E)}\ \text{average, by 20}}$.

See Also

2013 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
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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