Multiple choice

Speed of a boat in still water is 9 kmph and the speed of the stream is 1.5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. What is the total time taken by him?

  1. 18 hours

  2. 20 hours

  3. 22.5 hours

  4. 24 hours

  5. 26.3 hours

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

Speed downstream = 9 + 1.5 = 10.5 kmph, upstream = 9 - 1.5 = 7.5 kmph. Time to travel 105 km downstream = 105/10.5 = 10 hours. Return time = 105/7.5 = 14 hours. Total = 24 hours. Option D matches.