Question 889050
Ina Crespo rowed 7.5 miles down the Habashabee River in 1.5 hours, but the return trip took 2.5 hours. Find the rate Ina rows in still water and the rate of the current. Let x represent the rate Ina can row in still water and let y represent the rate of the current.
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let x=rate of rowboat in still water
let y=rate of current
x+y=rate of rowboat downstream
x-y=rate of rowboat upstream
distance/rate=travel time
..
7.5/(x+y)=1.5
7.5/(x-y)=2.5
..
1.5x+1.5y=7.5
2.5x-2.5y=7.5
..

7.5x+7.5x=37.5 (mult. by 5)
7.5x-7.5x=22.5 (mult. by 3)
add
15x=60
x=4
1.5y=7.5-1.5x=7.5-6=1.5
y=1
rate of rowboat in still water=4 mph
rate of current=1 mph