Statistics-Mean,median

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.

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