Question 317793
a motorboat can maintain a constant speed of 16 mile per hour relative to the water. the boat makes a trip upstream to a certain point in 20 minutes; the return trip takes 15 minutes. what is the speed of the current?

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upstream in 20 minutes = 1/3 hours
Down stream in 15 minutes = 1/4 hours
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let speed of current = x mph
upstream speed will be 16-x
down stream speed will be 16+x
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distance is same to & fro
distance= rate * time
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1/3 * (16-x) = 1/4*(16+x)
4*(16-x)=3*(16+x)
64-4x=48+3x
7x=16
x=2.28 mph