p is 3 times as old as q . in 11 years , p will be twice as old as q . how old was p 3 years ago ?
Choices.
A) 21 B) 24 C) 27 D) 30 E) 33

Rationale: p = 3 q so q = p / 3 p + 11 = 2 ( q + 11 ) = 2 ( p / 3 + 11 ) p / 3 = 11 p = 33 three years ago , p was 30 . the answer is d .
Answer: D