A boat running upstream takes 4 hours 24 minutes to cover a certain distance, while it takes 2 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?

Question: A boat running upstream takes 4 hours 24 minutes to cover a certain distance, while it takes 2 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?

Solution:
Let
The man's rate upstream be x kmph
The man's rate downstream be y kmph.
Distance covered upstream in 4 hrs 24 min = Distance covered downstream in 2 hrs.
x × (22/5) = y × 2
⇒ (22x)/5 = 2y
∴ y = (22x)/10

∴ Required ratio = (y + x)/2 : (y - x)/2
= (y + x) : ( y - x)
= {(22x)/10 + x} : {(22x)/10 - x}
= 32x/10 : 12x/10
= 32x : 12x
= 32 : 12
= 8 : 3