Nice Question..
The first five prime integers are 2, 3, 5, 7, and 11.
Set A: The average of the terms in Set A is 4, so the sum of the terms is (4)(3) = 12. There is only one
way for three of the first five primes to sum to 12: 2 + 3 + 7. Set A is {2, 3, 7}.
Set B: The product of the terms in Set B is divisible by 22, so 2 and 11 are terms in Set B. Set B is
{2, 11, x}, where x can be 3, 5, or 7.
We know that Sets A and B share one term: the 2. If x is either 3 or 7, the sets will share two terms. If
x is 5, the sets will only share one term.
Thus, we can rephrase the question as “Is x = 5?” A definite Yes or No answer leads to a definite
value answer for the number of shared terms (that is, Yes = 1, No = 2).
(1) SUFFICIENT: If the product of the terms in Set B is not divisible by 5, x ≠ 5 and the answer to
our rephrased question is a definite No.
(2) SUFFICIENT: If the product of the terms in Set B is divisible by 14, then 2 and 7 are terms in B.
Therefore, x = 7 and the answer to our rephrased question is a definite No.