Speed of a boat in standing 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. The total time taken by him is_________?
Q1. Speed of a boat in standing 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. The total time taken by him is_________?
Answer: 24 hours
Explanation: Downstream speed = 10.5 km/h, upstream = 7.5 km/h; total time = 105/10.5 + 105/7.5 = 10 + 14 = 24 hours.