Question 399868
Question: Traveling upstream on the Missouri River, a barge travels 35 mi in 7 h. Downstream, it travels the same distance in half the time. What is the rate of the barge in still water and the rate of the current.

Please use the variable r[rate of barge in still water] and c[rate of current] 
Could you please do the 4 steps process. If you do not know what the four step process is..it's 1st: let statement 2nd: equation 3rd: solve 4th: Writing the answer in a complete sentence. Thank you

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r= rate of barge in still water
c= rate of current.
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downstream rate = r+c
upstream rate = r-c 
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time downstream = 3.5 hours
time upstream = 7 hours
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d is same both directions = 35 miles

7(r-c)=35
/7
r-c=5......................1
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3.5(r+c)=35
7/2(r+c)=35
multiply by 2
7(r+c)=70
/7
r+c=10.....................2
add (1) & (2)
2r=15
/2
r=7.5 mph rate of bargein still water
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r-c=5
7.5-c=5
c=7.5-5
c=2.5 mph rate of current.
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