Tough and Tricky questions: Statistics.
Set X consists of prime numbers {3, 11, 7, A, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X?
Select.
A) 14
B) 16
C) 17
D) 20
E) 26

Rationale: since 11 y = even therefore y has to beevensince 11 is a odd integer ( even * odd = even ) similarly , y is the product of all integers in set x but all integers in set x are odd except the unknown a and since x contains only prime numbers , a has to equal to 2 . . . ( 2 is the only even prime number and the product of all prime numbers in set x has to be even , even * odd = even ) since you know value of a you can calculate the range = largest integer in the set minus smallest integer in the set = 19 - 2 = 17 answer is c
Answer: C