A alone can finish a work in 10 days which B alone can finish in 15 days. If they work together and finish it, then out of a total wages of Rs.3500, A will get:	Choose the correct choice from the following answers:
A) rs . 1200	B) rs . 1500	C) rs . 2100	D) rs . 2000	E) none of these

Rationale: "explanation : ratio of working days of a : b = 10 : 15 therefore , their wages ratio = reverse ratio = 15 : 10 therefore , a will get 15 units of ratio total ratio = 25 1 unit of ratio = 3500 / 25 = 140 so , a ’ s amount = 120 × 15 = rs . 2100 . answer : option c"
Answer: C