SOLUTION: A boat travelled 336 miles downstream and back. The trip downstream took 12 hours. The trip back took 14 hours. What is the speed of the boat in still water? What is the speed of

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Question 1018427: A boat travelled 336 miles downstream and back. The trip downstream took 12 hours. The trip back took 14 hours.
What is the speed of the boat in still water? What is the speed of the current?

Found 2 solutions by ankor@dixie-net.com, ikleyn:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A boat travelled 336 miles downstream and back.
The trip downstream took 12 hours. The trip back took 14 hours.
What is the speed of the boat in still water?
What is the speed of the current?
:
let s = boat speed in still water
let c = rate of the current
then
(s+c) = effective speed downstream
and
(s-c) = effective speed upstream
:
Write a distance equation for each way. dist = time * speed
12(s+c) = 336
14(s-c) = 336
we are in luck; we can greatly simplify both these equations
divide the first by 12, divide the 2nd by 14, and you have
s + c = 28
s - c = 24
--------------Addition eliminates c, find s
2s + 0 = 52
s = 52/2
s = 26 mph in still water
and
26 + c = 28
c = 28 - 26
c = 2 mph is the rate of the current
:
:
Check this using the 1st original equation
12(26 + 2) = 336
12(28) = 336
You can check this for yourself in the 2nd original equation

Answer by ikleyn(52794) About Me  (Show Source):
You can put this solution on YOUR website!
.
A boat traveled 336 miles downstream and back. The trip downstream took 12 hours. The trip back took 14 hours.
What is the speed of the boat in still water? What is the speed of the current?
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For similar travel and distance problems see the lesson Wind and Current problems in this site.