Standard Deviation.

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Standard Deviation.

by BTGmoderatorRO » Sun Jan 14, 2018 7:47 am
Median of price of the car is 52,000. which could be the median of the other two.

35000, 44000, x, y, 57000.

A. 38000
B. 47000
C. 48000
D. 51,000
E. 56,000

OA is E
Do I need a particular formula to solve this, an Expert contribution is needed urgently.

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by [email protected] » Sun Jan 14, 2018 10:48 am
Hi Roland2rule,

What is the source of this question? I ask because it's poorly-worded and there's an 'issue' with how it's designed.

From the given information, we're meant to assume that there are 5 total values (and it's certainly implied that the values are listed from least to greatest). If we're further meant to assume that the Median of the 5 values is 52,000, then that means one of 2 things:

1) Either both X and Y are 52,000
2) X is 52,000 and Y is bigger than 52,000 but no larger than 57,000

At the minimum, the median value of those 2 missing values is 52,000; at most, it's 54,500. None of those possible values is among the 5 choices though.

Given the listed correct answer, the value of one of the variables would have to be higher than 57,000 (based on the correct answer, Y would have to be 60,000). If the prompt had listed out the 5 values "out of order" (for example: X... 57,000.... 35,000....Y....44,000), then the correct answer would be easy to justify. As is, you would never see an Official GMAT question written in this way, so you might want to work with practice materials that are more realistic.

Final Answer: E

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