Question 313012
A boat goes 480 miles downstream in the same time it can go 400 miles upstream. The speed of the current is 4 miles per hour. Find the speed of the boat in still water
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r = boat's speed
480/(r+4) = 400/(r-4)
480*(r-4) = 400*(r+4)
80r = 3520
r = 44 mph