SOLUTION: I am totally confused on how to begin this problem, if someone could help it would be greatly appreciated. Junior's boat will go 15 miles per hour in still water. If he can go 12

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Question 180882This question is from textbook ELEMENTARY AND INTERMEDIATE ALGEBRA
: I am totally confused on how to begin this problem, if someone could help it would be greatly appreciated.
Junior'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?
This question is from textbook ELEMENTARY AND INTERMEDIATE ALGEBRA

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
You need to apply the distance formula:
d = rt
where
d is distance
r is rate or speed
t is time
.
Let x = speed of the current
then
12/(15+x) = 9/(15-x)
12(15-x) = 9(15+x)
4(15-x) = 3(15+x)
60-4x = 45+3x
60 = 45+7x
15 = 7x
15/7 = x
or
2.1429 mph = x