SOLUTION: In Slippery Creek, Janna can row 50 km downstream in 5 hours or she can row 25 km upstream in the same amount of time. Find the rate she rows in still water.
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Question 205787: In Slippery Creek, Janna can row 50 km downstream in 5 hours or she can row 25 km upstream in the same amount of time. Find the rate she rows in still water. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Janna can row 50 km downstream in 5 hours or she can row 25 km upstream in the
same amount of time.
Find the rate she rows in still water.
:
let s = speed in still water
let c = speed of the current
;
write two distance equation Dist = time * speed
:
5(s + c) = 50
5(s - c) = 25
:
Simplify, divide both equations by 5 and you have:
s + c = 10
s - c = 5
-------------addition eliminates c, find s
2s = 15
s =
s = 7.5 km/hr in still water
:
:
Is this true?
Find the speed of the current
s + c = 10
7.5 + c = 10
c = 10 - 7.5
c = 2.5 km/hr speed of the current
:
Check in the original equation
5(s + c) = 50
5(7.5 + 2.5) = 50
or
5(7.5 - 2.5) = 25
