Multiple choice

What is the speed of a boat in still water? Statement 1: The boat covers downstream a distance of 35km in 5 hours. Statement 2: The boat takes 7 hours to cover the 35km upstream.

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 or 2

  5. None of these

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

From statement 1, downstream speed = 35/5 = 7 km/h = boat speed + current speed. From statement 2, upstream speed = 35/7 = 5 km/h = boat speed - current speed. Adding both equations: 2 x boat speed = 12, so boat speed in still water = 6 km/h. Both statements together are necessary.