How many numbers do the sets S and T have in common?

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BTGModeratorVI wrote:
Fri Feb 28, 2020 9:55 am
How many numbers do the sets S and T have in common?

(1) S is a set of 10 numbers.
(2) T is a set of 100 numbers.

Answer: E
Source: Official Guide
Target question: How many numbers do the sets S and T in common?

Statements 1 and 2 combined
There are several scenarios that satisfy BOTH statements. Here are two:
Case a: S = {1,1,1,1,1,1,..1,1} and T = {0,0,0,0,0.....,0,0,0,0,0}. In this case, the answer to the target question is sets S and T have 0 numbers in common
Case b: S = {1,1,1,1,1,1,..1,1} and T = {1,0,0,0,0.....,0,0,0,0,0}. In this case, the answer to the target question is sets S and T have 1 number in common
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT

Answer: E

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