Rahim bought 52 books for Rs.1200 from one shop and 32 books for Rs.480 from another. What is the average price he paid per book ?  Choose the correct choice from the following answers:	A) s . 17	B) s . 18	C) s . 12	D) s . 20	E) s . 10

Rationale: "average price per book = ( 1200 + 480 ) / ( 52 + 32 ) = 1680 / 84 = rs . 20 answer : d"
Answer: D