SOLUTION: a tugboat can pull a boat 24mi downstream in 2h. going upstream, the tugboat can pull the same boat 16mi in 2h. what is the speed of the tugboat in still water? what is the speed o

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Question 819038: a tugboat can pull a boat 24mi downstream in 2h. going upstream, the tugboat can pull the same boat 16mi in 2h. what is the speed of the tugboat in still water? what is the speed of the current?
�how can you use the formula d=rt to help you solve the problem?
�how are the tugboats speeds when traveling upstream and downstream related to it's speed in the still water and the speed of the current?
I know it's not right, but I have tried this:
let x= speed of tugboat
let y= speed of current
upstream: 24=2x
downstream: 16=2x
thank you in advance for the help, it's appreciated!
Answer by josgarithmetic(39623) (Show Source):
You can put this solution on YOUR website!
Tugboat speed in still water is r.
Let current speed be c. Upstream means AGAINST the direction of the current and the tugboat would be able to ga at r-c. Downstream is WITH the direction of current and so speed for the tugboat is r+c. I used different variables here than you used.

See if a data table helps.
__________________speed__________time________distance
UP________________r-c____________2___________24
DOWN______________r+c____________2___________16

Just as you have r*t=d, speed*time=distance.
We can use this to make two equations.
and
Dividing both equations by 2,
and
Two equations in two unknowns.

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Usage of Elimination Method will be uncomplicated, and you should easily find r=10.