SOLUTION: Tom's boat will go 15 miles per hour in still water. If he can go 12 miles downstream in the same amount of time as it takes to go 9 miles upstream, then what is the speed of th

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Question 398290: Tom's boat will go 15 miles per
hour in still water. If he can go 12 miles downstream in the
same amount of time as it takes to go 9 miles upstream,
then what is the speed of the current?

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Tom's boat will go 15 miles per
hour in still water. If he can go 12 miles downstream in the
same amount of time as it takes to go 9 miles upstream,
then what is the speed of the current?
...
speed of current = x mph
boat speed = 15 mph
...
t = d/r
t upstream = t downstream
9/(15-x)= 12/(15+x)
9(15+x)=12(15-x)
/3
3(15+x)=4(15-x)
45+3x=60-4x
3x+4x=60-45
7x=15
/7
x= 2.14 mph current speed
...
m.ananth@hotmail.ca