Question 554859
Traveling downstream a certain boat went 11 mph. Traveling upstream it only went 1 mph. Find the current and the speed of the boat if there were no current.
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Down speed = b + c (boat + current)
Up speed = b - c (boat - current)
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b + c = 11
b - c = 1
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2b = 12
b = 6 mi/hr
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c = 5 mi/hr
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The boat's speed is the average, = (11+1)/2 = 6
The current is the difference, 11 - 6 = 5