Question

A boat moves downstream at the rate of one km in 5 minutes and upstream at the rate of 4 km an hour. what is the velocity of the current?

Answer 1

Speed downstream = 1/(5/60)=12 km/hr

Speed upstream =4/1 = 4 km/hr

velocity of the current =1/2(12−4)=4 km/hr

Answer 2

Answer: The velocity of the current is 4 km/hr.

Step-by-step explanation:

Since we have given that

Speed of downstream = 1 km in 5 minutes

Speed would be

$\dfrac{1}{5}\times 60=12\ km/hr$

Speed of upstream = 4 km/hr

We need to find the velocity of the current.

So, Velocity of current would be

$\dfrac{Downstream-Upstream}{2}\\\\=\dfrac{12-4}{2}\\\\=\dfrac{8}{2}\\\\=4\ km/hr$

Hence, the velocity of the current is 4 km/hr.