P is 40% more efficient than Q. P can complete a work in 24 days. If P and Q work together, how many days will it take to complete the same work?  Pick one:
A) 8	B) 9	C) 11	D) 14	E) 15

Rationale: "the work done by p in 1 day = 1 / 24 let work done by q in 1 day = q q × ( 140 / 100 ) = 1 / 24 q = 100 / ( 24 × 140 ) = 10 / ( 24 × 14 ) the work done by p and q in 1 day = 1 / 24 + 10 / ( 24 × 14 ) = 24 / ( 24 × 14 ) = 1 / 14 p and q together can do the work in 14 days . the answer is d ."
Answer: D