Median Question

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Median Question

by KICKGMATASS123 » Wed Jul 29, 2009 10:43 am
Tom, Jane, and Sue each purchased a new house. The average (arithmetic mean) price of the three houses was $120,000. What was the median price of the three houses?

(1) The price of Tom’s house was $110,000.
(2) The price of Jane’s house was $120,000.


OA is B

I fell for the trap answer C how do i avoid this trap the next time i see a similar question.
Source: — Data Sufficiency |

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Re: Median Question

by qwe12 » Wed Jul 29, 2009 9:21 pm
KICKGMATASS123 wrote:Tom, Jane, and Sue each purchased a new house. The average (arithmetic mean) price of the three houses was $120,000. What was the median price of the three houses?

(1) The price of Tom’s house was $110,000.
(2) The price of Jane’s house was $120,000.


OA is B

I fell for the trap answer C how do i avoid this trap the next time i see a similar question.
consider 1) you can come up with a configuration that looks like this

110,000 125,000 125,000
or
110,000 120,000 140,000

so 2 different medians. NOT SUFFICIENT

consider 2) something, 120,000, something

100,000, 120,000, 240,000

120,000 120,000 120,000

whatever you do, 120,000 stays put.

SUFFICIENT

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by shahdevine » Thu Jul 30, 2009 8:05 am
There are three terms under observation: price of Tom's house, Jane's House and Sue's house. Once you know one of the actual prices equals the average price of the house you have found your median. Average means the middle. Statement 2 gives you the actual middle value. At worst, Tom and Sue's house could equal that value as well. But we are looking for the median, which is the middle position. Not the mean.

hope helps