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Statistics-Mean,median

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Statistics-Mean,median

by ash4gmat » Wed Apr 27, 2016 7:57 am
Q.Set A has 2 +ve integers with median of 5.Set B has 3 +ve int with mean of 3.

Is it True that mean of combined set is less than 4.

For this If I considered 2 nos in set A as 6 & 7, will that be wrong?This assumption will make this statement false.
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by [email protected] » Wed Apr 27, 2016 8:11 am
Hi ash4gmat,

The two pieces of information that you're given about Set A and Set B are rather specific, so it might help if you deal with them one at a time:

1) Set A has 2 POSITIVE integers with a MEDIAN of 5.

Since we have a median of 5 and we're dealing with just 2 positive integers, the median will be the AVERAGE of the two numbers. The possible combinations are limited. They could be...

5 and 5
4 and 6
3 and 7
2 and 8
1 and 9

Notice that the sum is ALWAYS 10.

2) Set B has 3 POSITIVE integers with a MEAN of 3

Since we have a mean of 3, and 3 terms, the SUM of those terms must be 9.

When we combined those two groups, we'll end up with 5 terms that have a sum of 19. Therefore, the AVERAGE of the group will be 19/5 = 3.8

Your example is not correct, since 6 and 7 will NOT produce a median of 5.

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Rich
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by ash4gmat » Wed Apr 27, 2016 8:38 am
Thanks Rich.

It was an stupid error.
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