Question

A boat has to travel upstream 20 km distance from point X of a river to point Y. The total time taken by boat in travelling from point X to Y and Y to X is 41 minutes 40 seconds. What is the speed of the boat?

• A. 66 kmph
• B. 72 kmph
• C. 48 kmph
• D. Data inadequate

Answer 1

Answer:

D. Data inadequate

Let 'x' be the speed of the boat and 'y' the speed of the current.

∴ $\frac{20}{x-y}+\frac{20}{x+y}=\frac{25}{36}$

In this equation there are two variables, but only one equation, so, the value of ‘x’ cannot be determined.