Multiple choice

A boat covers a distance of 40 km in 8 hours against the stream and covers a distance of 36 km in 6 hours with the stream. Find the speed of the boat in still water.

  1. 6.5 km/hr

  2. 6 km/hr.

  3. 5 km/hr.

  4. 5.5 km/hr.

  5. 4 km/hr.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Against stream: speed = 40/8 = 5 km/hr (boat - stream). With stream: speed = 36/6 = 6 km/hr (boat + stream). Adding: 2 × boat = 11, so boat = 5.5 km/hr. Option B (6 km/hr) is the downstream speed, not still water speed.