The simple interest on a certain sum of money at 4 percent per annum for 4 years is TK. 87.5 more than interest on the same sum for 3 years at 5 percent per annum. Find the sum of money.

Correct Answer: TK. 8,750
Speed of the first train = 150/15 = 10 mps. speed of the second train = x mps. According to the question: x + 10 = (150 + 150)/8 x = 27.5 mps = 27.5 × 3600/1000 = 99 kmph. Ans: D