Bunuel wrote:
If all members of Set X are positive integers, what is the range of Set X?
(1) The positive difference between the square of the largest number in Set X and the square of the smallest number in Set X is 99.
(2) The sum of the largest number in Set X and the smallest number in Set X is 11.
Let largest number be 'a' and smallest number be 'b'.
a-b?
Statement 1:
a^2 - b^2 = 99
(a+b)(a-b)=99
If a=50 and b =49, then a-b=1;
If a=10, and b =1, then a-b = 9;
Insufficient
Statement 2:
a+b=11,
Clearly insufficient
Statement 1&2:
11*(a-b)=99
So a-b=9
C
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55% (01:13) correct 
