Not sure of this median problem

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by theCodeToGMAT » Mon Jan 27, 2014 9:13 am
(3 + 10 + 3 + 5 + 3) = 24
Even number
So, 24/2 = 12 & 13

12th Element = 2
13th Element = 2

So, Median = (2+2)/2 = 2

[spoiler]{B}[/spoiler]?
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by Brent@GMATPrepNow » Mon Jan 27, 2014 12:07 pm
Another approach is to list the distribution of values that are 1 or greater.
We get: {1,1,1,2,2,2,2,2,2,2,2,2,2,3,3,3,4,4,4,4,4,5+,5+5+}
Since there is a EVEN number of values, we have TWO middlemost values. So, the median is the average (mean) of those two values.

Median = (2 + 2)/2
= [spoiler]2 = B[/spoiler]

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by [email protected] » Mon Jan 27, 2014 2:04 pm
Hi shibsriz,

Both Brent and Rahul have properly explained the math behind this question; there's a visual "shortcut" to the question that I'll walk you through.

Since the question asks for the median of the group, we're either looking for the 1 middle number (if the total number of terms is odd) or the average of the 2 middle numbers (if the total number of terms is even).

In the chart, you can see that there are LOTS more 2s than any other number. There are 7 numbers that are less than two and 11 numbers that are greater than two. Those 11 bigger numbers would be offset by the 7 smaller numbers and 4 of the twos. Everything left would be a 2, so whether there's one term or two terms, the median will still be 2.

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