Ok, this one was in my kaplan math workbook
, but there must be a misprint in the answers, because the answer to this one was omitted...
S is a set of positive integers such that if integer x is a member of S, then both x^2
are also in S. If the only member of S that is neither the square nor the cube of another member of S is called the source integer, is 8 in S?
(1) 4 is in S and is not the source integer
(2) 64 is in S and is not the source integer
I think the answer is E...what does everyone else think?
If 4 is in S and is not the source integer then 2 must be present in S => 2^3 = 8 must also be present in S.
If 64 is in S and is not the source integer then it could either be due to 4 as a source integer or 2 as a source integer.
If 2 is the source integer then 8 is in S else its not.