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systems of equations algebra help?
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A Mississippi riverboat can travel 30 kilometers downstream in 3 hours and can make the return trip in 5 hours. Find the speed of the boat in still water.
Could use some help with this!
Thanks!
1 Answer
- DambarudharLv 77 years agoFavorite Answer
Speed of the boat in still water = u kph
Speed of the water current = v kph
Distance traveled = d = 30 km
Time taken to travel downstream = t1 = 3 hr
Time taken to travel upstream = t2 = 5 hr
We have the following equations :
Downstream : (u + v)t1 = d
=> (u + v)*3 = 30
=> u + v = 30/3 = 10 -------- (1)
Upstream : (u - v)t2 = d
=> (u - v)*5 = 30
=> u - v = 30/5 = 6 ------- (2)
Adding (1) and (2), we have : 2u = 16
=> u = 16/2 = 8
=> Speed of the boat in still water = 8 kph ----- Answer
=> Speed of the water current = 2 kph