Correct question is;
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:
Total time = 24 hours
Step-by-step explanation:
We are given;
Speed of a boat in standing water = 9 kmph
Speed of the stream = 1.5 kmph
Distance rowed by the man; d = 105 km
He now came back to his starting point.
Thus, we can say that;
Speed upstream; V_up = 9 - 1.5 = 7.5 kmph
Speed downstream; V_down = 9 + 1.5 = 10.5 kmph
Now, we know that;
time = distance/speed
Thus;
Total time = time taken upstream + time taken downstrem
Total time = (105/7.5) + (105/10.5)
Total time = 14 + 10
Total time = 24 hours
