Sandy is younger than Molly by 12 years. If the ratio of their ages is 7:9, how old is Sandy?  Pick.
A) 42	B) 49	C) 56	D) 63	E) 70

Rationale: let sandy ' s age be 7 x and let molly ' s age be 9 x . 9 x - 7 x = 12 x = 6 sandy is 42 years old . the answer is a .
Answer: A