1983 AHSME Problems/Problem 25

Problem: If 60^a=3 and 60^b=5, then 12^[(1-a-b)/2(1-b)] is

(A):sqrt3 (B): 2 (C): sqrt5 (D): 3 (E): sqrt12

Solution: We know that a=log 3 and b=log 5

                                              60                       60

Answer:B