SOLUTION: A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 990601: A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current r in miles per hour.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A boat can travel 28 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current r in miles per hour.
---------
With current DATA:
dist = 100 miles ; rate = 28+c mph ; time = 100/(28+c)
----
Against current DATA:
dist = 80 miles ; rate = 28-c mph ; time = 80/(28-c)
-----
Equation:
time = time
100/(28+c) = 80/(28-c)
------
100(28-c) = 80(28+c)
----
100*28 - 100c = 80*28 + 80c
----
180c = 20*28
----
c = 3.11.. mph (rate of the current)
-----------
Cheers,
Stan H.
-----------