A sum was put at simple interest at a certain rate for 5 years Had it been put at 6% higher rate, it would have fetched 90 more. Find the sum.	Choose one.
A) 90	B) 100	C) 200	D) 300	E) 400

Rationale: "difference in s . i . = p × t / 100 ( r 1 − r 2 ) ⇒ 90 = p × 5 x 6 / 100 ( ∵ r 1 - r 2 = 2 ) ⇒ p = 90 × 100 / 5 x 6 = 300 answer d"
Answer: D