- A3 km/h
- B6 km/h
- C4 km/h
- D1.5 km/h
Step-by-Step Solution
Let D = 4k, U = 3k. Boat = 3.5k = 21 so k = 6: D = 24, U = 18. Current = 3 km/h.
Answer: A) 3 km/h
A motorboat's downstream and upstream speeds are in the ratio 4 : 3. If its still-water speed is 21 km/h, what is the speed of the current?
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