A boat’s speed in still water is 22 km/h, while the river is flowing with a speed of 8 km/h and the time taken to cover a certain distance upstream is 4 hours more than the time taken to cover the same distance downstream. Find the distance.

105 km

We know that,

Upstream Speed = Speed of Boat – Speed of current

Downstream Speed = Speed of Boat + Speed of current

Given,

Difference in time = 4 hours

Still water speed = 22 km/h

Stream speed = 8 km /h

Upstream speed = ( 22 -8) = 14

Downstream speed = ( 22 +8) = 30

According to the given question ,

Now, let the required distance be D then,

\(\frac{D}{22 - 8}\) - \(\frac{D}{22 + 8}\) = 4

On solving,

 16D = 420× 4 

D = 105 km.