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A river is flowing from west to east direction with speed of 9 km h –1 . If a boat capable of moving at a maximum speed of 27 km h –1 in still water, crosses the river in half a minute, while moving with maximum speed at an angle of 150° to direction of river flow, then the width of the river is :

1. 112.5 m
2. 75 m
3. 300 m
4. 112.5 × 3 m

Correct answer: 112.5 m

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