SOLUTION: A riverboat can travel 30km downstream in 3 hrs & can make the return trip in 5 hrs. Find the speed of the boat and the speed of the current.

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: A riverboat can travel 30km downstream in 3 hrs & can make the return trip in 5 hrs. Find the speed of the boat and the speed of the current.      Log On


   

Question 773927: A riverboat can travel 30km downstream in 3 hrs & can make the return trip in 5 hrs. Find the speed of the boat and the speed of the current.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The return trip is upstream, the lesser rate. The downstream trip is the greater rate.

Let r = riverboat speed if no current.
Let c = speed of the current.

DIRECTION_______speed_________time______distance
UPSTREM_________r-c___________5__________30
DOWNSTREAM______r+c___________3__________30

Basic concept is rate*time=distance.
%28r-c%295=30 and %28r%2Bc%293=30
Two equations and two unknowns, r and c. Solve the system.