SOLUTION: Jane took 30 min to drive her boat upstream to water-ski at her favorite spot. Coming back later in the day, at the same boat speed, took her 10 min. If the current in that part of

Question 780612: Jane took 30 min to drive her boat upstream to water-ski at her favorite spot. Coming back later in the day, at the same boat speed, took her 10 min. If the current in that part of the river is 5 km per hr, what was her boat speed in still water?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = the speed of the boat in km/hr in still water
Let = the one-way distance the boat travels in km
Going upstream:

Going downstream:

----------------------
By substitution:

Multiply both sides by

The speed of the boat in still water is 10 km/hr
check:

km
and

km
OK

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