Question
A boat can travel upstream at 12 km/h and downstream at
18 km/h. What is the speed of the boat in still water?Solution
Let the speed of the boat in still water be x km/h and speed of current be y km/h. Then, x - y = 12 (upstream), x + y = 18 (downstream). Adding both equations: 2x = 30 β x = 15 km/h. Answer: a) 15 km/h.
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