A boat takes 16 minutes and 24 minutes to cover a certain distance downstream and upstream, respectively. If the speed of the boat in still water is 15 km/h, find the speed of the stream.

3 km/h

We know that,

Upstream Speed = Speed of Boat – Speed of current

Downstream Speed = Speed of Boat + Speed of current

Given,

A boat takes 16 minutes and 24 minutes to cover a certain distance downstream and upstream, respectively.

The speed of the boat in still water = 15 km/h.

Let the distance be D and the speed of the stream be S km/h.

Upstream speed = (15 - S) km/h

Downstream speed = (15 + S) km/h

According to the concept,

\(\frac{D}{15 + R}\) = \(\frac{16}{60}\)

D = \(\frac{240 + 16D}{60}\)----(A)

And,

\(\frac{D}{15 - R}\) = \(\frac{24}{60}\)

D = \(\frac{360 - 16D}{60}\)----(B)

From A and B,

= 240 + 16D = 360 - 24D

= 40D = 120

= D = 3