- A9 km/h
- B8.8 km/h
- C9.6 km/h
- D10 km/h
Step-by-Step Solution
Average speed for equal distances = km/h. It is NOT the simple average 10 km/h — more time is spent on the slow leg.
Answer: C) 9.6 km/h
A launch with a still-water speed of 10 km/h goes upstream and returns to its starting jetty on a river flowing at 2 km/h. What is its average speed for the whole trip?
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