Question

A boat goes upstream at 36 km/h and downstream at 40 km/h. The distance covered in each trip being the same, find the speed of boat in still water.

• A. 45 km/h
• B. 34 km/h
• C. 38 km/h
• D. 2 km/h

Answer 1

Answer:

C. 38 km/h

$\text{Speed of boat in still water} = \frac{\text{Downstream Speed} + \text{Upstream Speed}}{2}$

Given:

• Upstream Speed ($u$) = $36 \text{ km/h}$

• Downstream Speed ($d$) = $40 \text{ km/h}$

$\text{Speed in still water} = \frac{40 + 36}{2}$

$\text{Speed in still water} = \frac{76}{2}$

$\text{Speed in still water} = 38 \text{ km/h}$

The speed of the boat in still water is $38 \text{ km/h}$