Engineering Board Exam Reviewer · Motion Problems · medium
A boat travels 30 km downstream in 2 hours and returns upstream in 3 hours. Find the speed of the current.
- 5 km/h
- 12.5 km/h
- 2.5 km/h
- 25 km/h
Answer
C. 2.5 km/h
Solution
Downstream speed =30/2=15 km/h and upstream speed =30/3=10 km/h. The current is half the difference: 15-10/2=2.5 km/h.
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