Multiple choice

A boat travels 24 km upstream in 6 hours and 20 km downstream in 4 hours. Then, what is the ratio of the speed of the boat in still water and the speed of the current?

  1. 4: 3

  2. 5: 2

  3. 9: 1

  4. 2: 1

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

Upstream: boat speed - current = 24/6 = 4 km/h. Downstream: boat speed + current = 20/4 = 5 km/h. Solving: boat speed = (4+5)/2 = 4.5 km/h, current = (5-4)/2 = 0.5 km/h. Ratio = 4.5:0.5 = 9:1.