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A Boat covers 12 km in 1 h in still water. It takes four times the time in covering the same distance against the current. What is the speed of the current?

A7 km/hr

B8 km/hr

C9 km/hr

D10 km/hr

Answer:

C. 9 km/hr

Read Explanation:

Speed Upstream = Speed of boat in still water - Speed of current Speed of boat in still water = 12 km/h Speed against the current = 12/4 = 3 km/h Let the speed of the current be x. ⇒ 12 - x = 3 ⇒ x = 9km/h


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