The speed at which a man can row a boat in still water is 15 kmph. If he rows downstream, where the speed of current is 3 kmph, what time will he take to cover 15 metres?
Select
A) 5	B) 10	C) 3	D) 12	E) 6

Rationale: "speed of the boat downstream = 15 + 3 = 18 kmph = 18 * 5 / 18 = 5 m / s hence time taken to cover 60 m = 15 / 5 = 3 seconds . answer : c"
Answer: C