SOLUTION: A boat travels 168 miles downstream then turns around and travels 168 miles back to the starting position (336 miles total). The trip downstream took 12 hours while the trip back t

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Question 908598: A boat travels 168 miles downstream then turns around and travels 168 miles back to the starting position (336 miles total). The trip downstream took 12 hours while the trip back took 14 hours. Solve as a linear equation and find the speed of the boat when traveling downstream and the speed of the boat when traveling back.
Found 2 solutions by ewatrrr, richwmiller:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
168mi%2F%2812hr%29= downstream mph
168mi%2F%2814hr%29= upstream mph

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
r*t=d
with the current
(r+c)*12=168
(r+c)=168/12
r+c=14
against the current
(r-c)*14=168
(r-c)=168/14
r-c=12
r+c=14
add
r+r=14+12
2r=26
r=13 mph rate
13-c=12
c=13-12
c=1 mph current
check
(13+1)*12=168
14*12=168
168=168
ok
(r-c)*14=168
(13-1)*14=168
12*14=168
168=168
ok