Rational Expression Word Problem

Question

In his boat, Jerry can travel 24 miles upstream in the same time that it takes to travel 36 miles downstream. If the rate of the current is 2 mph, what is the rate of the boat in still water?

Answer 1

Trip               D     R      T

upstream     24    r-2    24/(r-2)

downstr.       36    r+2  36/(r+2)   where r is inherent speed of boat w/o current.

 

The above "DRT" chart uses the fundamental D = R•T principle of uniform motion.

 

Set the two times equal & solve that equation.