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A man crosses a river in a boat. If he c...

A man crosses a river in a boat. If he cross the river in minimum time he takes `10 min` with a drift `120 m.` If he crosses the river taking shortest path, he takes `12.5 min,` find
(a) width of the river
(b) velocity of the boat with respect to water
(c) speed of the current

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The correct Answer is:
200m, 20 m/min, 12 m/min
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