A merchant has 120kg of rice. He sells a part of it at a profit of 10 % and the rest at a profit of 25%. He gains 15% on the whole. The quantity of rice sold at a profit of 25% is
- A. 50 kg
- B. 55 kg
- C. 40 kg
- D. 30 kg
Answer: C. 40 kg
Explanation: By allegation rule: ratio of rice sold at 10% to 25% is (25 − 15) : (15 − 10) = 10 : 5 = 2 : 1. Amount sold at 25% profit = (1/3) × 120 kg = 40 kg.