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by NeilWatson » Wed Apr 16, 2014 3:56 pm
Two sets, A and B, have the same number of elements and the same median. Which set has the higher average?

1) In set A, 75% of the numbers are greater than or equal to the median. In set B 50% of the numbers are greater than or equal to the median.

I know this is not sufficient but I have a question on the concept behind this problem. Is it right that the median has nothing to do with figuring out average unless it is an evenly spaced set, in which case the median would be equal to the median?

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by [email protected] » Thu Apr 17, 2014 12:47 am
Hi NeilWatson,

You are correct in that the median of a group of numbers essentially has no impact on the average of that group of numbers. IF you're dealing with a set of evenly spaced values (1, 2, 3, 4, 5 for example), then the median DOES equal the average.

You can rely on these concepts and definitions regardless of the question type. The GMAT can test you on "statistical concepts" in either PS or DS questions. If you're given data (numbers), then use them. If you're given unknowns, then consider the possibilities based on the restrictions implied by the statistical terms that are used.

GMAT assassins aren't born, they're made,
Rich
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