[Forest Guard, 2022]

5. A boat sails 20 km of a river towards upstream in 4 hours. How long it will take to cover the same distance downstream, if the Speed of current is one-fifth the speed of the boat in still water ?

1. 4 hours

2. 2 hours 40 minutes

3. 3 hours 20 minutes

4. 5 hours

Correct Answer :

2 hours 40 minutes