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 20 km in 20 hours. How much time he would have saved if the direction of tide has not changed?  Choose the correct choice from the following.
A) 2  B) 8  C) 1  D) 6  E) 16

Rationale: "explanation : he covered 5 km in 1 hour , so he might cover 20 km in 4 hours . but he took 20 hours . he would have saved 20 â € “ 4 = 16 hours . answer : e"
Answer: E