A boat goes 12 km in 1 h in still water. It takes thrice time in covering the same distance against the current. Find the speed of the current.?

8 km/h
12 km/h
6 km/h
7 km/h

Correct Answer: 8 km/h

Explanation:

Speed of a boat in still water = distance / time = 12/1 = 12 km/h
Speed against the current = 12/3 km/h
Let the speed of the current = x km/h
According to the question,
12 - x = 4
⇒ x = 8 km/h

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