A man can row a distance of 5 km in 60 min with the help of the tide. The direction of the tide reverses with the same speed. Now he travels a further 30 km in 10 hours. How much time he would have saved if the direction of tide has not changed?	Select the correct option:	A) 2	B) 8	C) 4	D) 6	E) 5

Rationale: "explanation : he covered 5 km in 1 hour , so he might cover 30 km in 6 hours . but he took 10 hours . he would have saved 10 â € “ 6 = 4 hours . answer : c"
Answer: C