SOLUTION: show all work using the 5-step method to solve: a sailboat travels 20 miles downstream in 4 hours. it returns in 5 hours. find the speed of the sailboat in still water and the r

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Question 473735: show all work using the 5-step method to solve:
a sailboat travels 20 miles downstream in 4 hours. it returns in 5 hours. find the speed of the sailboat in still water and the rate of the current.
Found 3 solutions by ccs2011, ewatrrr, Alan3354:
Answer by ccs2011(207)   (Show Source):
You can put this solution on YOUR website!
Distance = rate*time denoted as d=rt
The boat traveled the same distance of 20 miles both upstream and downstream.
Let s be speed of boat in still water, let c be rate of current.
Downstream boat goes faster so its speed is s+c, Upstream its s - c.
Set up equations:
20 = 4(s+c)
20 = 5(s-c)
Distribute
20 = 4s + 4c
20 = 5s - 5c
Using substitution
5s - 5c = 4s + 4c
Solve for s: (Subtract 4s on both sides, Add 5c on both sides)
s = 9c
Now substitute 9c in for s:
20 = 4(9c) + 4c
20 = 36c + 4c
20 = 40c
1/2 = c
--> s = 9(1/2) = 9/2 = 4.5
Therefore the boat travels 4.5 mph in still water and the rate of the current is 0.5 mph

Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!

Hi,
Let s and c represent the rate of the sailboat(still water) and the rate of
the currecnt respectively
Question states*** Note D = r/t OR r = D/t
s+c = 20mi/4hr = 5mph
s-c = 20mi/5hr = 4mph
2s = 9mph
s = 4.5mph and c = .5mph (5mph- 4.5mph = .5mph)

Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
a sailboat travels 20 miles downstream in 4 hours. it returns in 5 hours. find the speed of the sailboat in still water and the rate of the current.
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20/4 = 5 mph
20/5 = 4 mph
The speed of the boat is the average = 4.5 mph
The current is the difference = 0.5 mph
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It's odd that there's no mention of the wind for a sailboat.