The speed of a boat in still water is 5 km/hr and the speed of the stream is 1 km/hr. A man rows to a place at a distance of 24 km and comes back to the starting point. Find the total time taken by him.
A8 hr
B10 hr ✓ Correct
C12 hr
D15 hr
Correct answer: (B) 10 hr
Explanation
The total time taken is 10 hours.
Downstream speed = 5 + 1 = 6 km/hr, upstream = 5 - 1 = 4 km/hr.
Downstream time = 24 / 6 = 4 hr.
Upstream time = 24 / 4 = 6 hr.
Total = 4 + 6 = 10 hr.
Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.
Practise on Mcqkart →🎓 Book an expert →