<PRE><B>Question 1028009</B>
A boat can travel 31 mph in still water. If it travels 222 miles with the current in the same length of time it travels 150 miles against the current, what is the speed of the current?
let speed of water current is x mph
speed with the current =X+31 mph
time =distance/time =222/x+31 hrs 
speed against the current =31-x mph
time =150/31-x    both time are equal given 
150/31-x=222/31+x
150(31+x)=222(31-x)
4650+150x=6882-222x
150x+222x=6882-4650
372x=2232
x=6
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