11. The number N equals 7,2G2, the tensâ€™ digit being represented by G. What is the value of G?
(1) N is divisible by 4
(2) N is divisible by 9
I am lost as to how divisibility can solve this problem.
Apply the rules of divisibility.
1) for N to be divisible by 4, the number G2 must be divisible by 4 (why?). Hence, G could be any odd integer so (1) is not sufficient.
2) for N to be divisible by 9, the digits in N must add up to a multiple of 9. Only 7 meets this criterion, hence 2 is sufficient and the answer is (B).
Former Senior Instructor, Manhattan GMAT and VeritasPrep
Vice President, Midtown NYC Investment Bank, Structured Finance IT
MFE, Haas School of Business, UC Berkeley, Class of 2005
MBA, Anderson School of Management, UCLA, Class of 1993