<PRE><B>Question 1074469</B>
speed*time=distance
speed of boat is x
(x+6)*4=4(x+6) miles
(x-6)*5=5(x-6) miles
The two distances are equivalent.  Set them equal to each other and distribute.
4x+24=5x-30
x=54 mph boat speed ANSWER
downstream at 60 mph for 4 hours is 240 miles
upstream at 48 mph for 5 hours is 240 miles
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