Question

32. A boat takes two hours to travel 8 km down and 8 km up the river when the water is still. How much time
will the boat take to make the same trip when the river starts flowing at 4 kmph?
(1) 2 hour
(2) 2 hour 40 minute
(3) 3 hour
(4) 3 hour 40 minute​

Answer 1

Answer:

Answer: Speed of boat in still water = 16/2 = 8 km/hr. time for travelling 8 km downstream = 8/(8+4) = (2/3) hr = 40 min.