A boat running upstream takes 8 hours 48 min to cover a certain distance while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and the speed of water current respectively?
Answer: C
Let the speed of boat be x km/hr and speed of stream be ykm/hr.
44/5 × (x -y) = 4x (x +y)
=> 44(x-y) = 20 (x+y)
=>11 (x-y) = 5 (x +y)
=> 6x =16 y
=> x/y = 16/6 = 8/3
=> x : y = 8 : 3