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jammuna rode a boat a to b and back to a in a totl time of 12 hrs out of which she rode for 5 hrs in the direction of the flow of the stream the distance between a and b is 70 km find the speed of the stream
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This is a better problem description:
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Jammuna rode a boat from A to B and back in total time of 12 hours. Five hours were ridden in the stream's direction, and the A to B distance was 70 kilometers. Find the speed of the stream.
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SPEED TIME DISTANCE
A to B r+c 5 70
B to A r-c 7 70
TOTAL 12
RATE x TIME = DISTANCE
From that system, this simpler system should be clear:
Question asks for c.
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