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A motorboat can maintain a constant speed of 34 miles per hour relative to the water.
The boat makes a trip upstream to a certain point in 35 minutes;
the return trip takes 33 minutes. What is the speed of the current?
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Let "c" be the speed of the current, in miles per hour.
Then the rate of the boat moving upstream is (34-c) miles per hour;
the rate of the boat moving downstream is (34+c) miles per hour.
The distance of both trips is the same, so we write the distance equation
= .
Multiply both sides by 60 and simplify
(34-c)*35 = (34+c)*33
34*35 - 35c = 34*33 + 33c
34*35 - 34*33 = 33c + 35c
34*(35-33) = 68c
34*2 = 68c
c = = = 1.
ANSWER. The speed of the current is 1 mile per hour.
Solved.