SOLUTION: 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 th

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: 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 th      Log On


   

Question 285810: 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?
Found 2 solutions by checkley77, richwmiller:
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
336/12=28 mph down stream.
336/14=24 mph up stream.
(28-24)/2=4/2=2 mph is the current speed.
28-2=26 mph for the boat speed.
24+2=26 mph ditto.


Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
(r+c)*12=336
(r-c)*14=336
divide both by 2
(r+c)*6=168
(r-c)*7=168
(r+c)*6=(r-c)*7
6r+6c=7r-7c
13c=r
substitute 13c for r in equation one
14c*12=336
7c*12=168
7c*6=84
42c=84
c=2
r=26