- A2.5 hours
- B1.5 hours
- C3 hours
- D2 hours
Step-by-Step Solution
Downstream = 14 km/h; upstream = km/h. Time = 21 ÷ 8.4 = 2.5 hours.
Answer: A) 2.5 hours
A launch goes 28 km downstream in 2 hours, and its upstream speed is 60% of its downstream speed. How long will 21 km upstream take?
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