SOLUTION: Traveling downstream a certain boat went 17 km/h. Traveling upstream it only went 5 km/h. What is the speed of the current? How fast would the boat go if there were no current?

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Question 896523: Traveling downstream a certain boat went 17 km/h. Traveling upstream it only went 5 km/h. What is the speed of the current? How fast would the boat go if there were no current?
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
Traveling downstream a certain boat went 17 km/h.
Traveling upstream it only went 5 km/h.
What is the speed of the current?
How fast would the boat go if there were no current?
:
let s = the boat speed in still water
let c = the rate of the current
then a simple equation for each way
s + c = 17
s - c = 5
-------------Adding eliminates c, find s
2s = 22
s = 22/2
s = 11 km/h in still water
then
11 + c = 17
c = 17 - 11
c = 6 km/h is the rate of the current
:
:
Check this in the 2nd equation
11 - 6 = 5