SOLUTION: A motorboat takes 5 hours to travel 100 km going upstream. The return trip takes 2 hours going downstream. What is the rate of the boat in still water and what is the rate of the c
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Question 1130823: A motorboat takes 5 hours to travel 100 km going upstream. The return trip takes 2 hours going downstream. What is the rate of the boat in still water and what is the rate of the current?
Rate of the boat in still water:
Rate of the current: Found 2 solutions by josmiceli, MathTherapy:Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! let = the speed of the boat in still water in km/hr
Let = the speed of the current in km/hr
Going upstream:
(1)
Going downstream:
(2)
-------------------------------
(1)
(2)
Multiply (1) by , multiply
(2) by , and add the equations
-----------------------------------------------
(2)
(1)
-------------------------------
and
(2)
(2)
(2)
-----------------------------
Rate in still water: 35 km/hr
Rate of the current: 15 km/hr
You can put this solution on YOUR website!
A motorboat takes 5 hours to travel 100 km going upstream. The return trip takes 2 hours going downstream. What is the rate of the boat in still water and what is the rate of the current?
Rate of the boat in still water:
Rate of the current:
Let boat speed, in still water, be S, and speed of current, C
Then we get the following system of equations for the 2 speeds:
2S = 70 ------- Adding eqs (ii) & (i)
Speed of boat, or
Speed of current, or