SOLUTION: A tugboat can pull a boat 24 miles downstream in 2 hours. Going upstream, the tugboat can pull the same boat 16 miles in 2 hours. What is the speed of the tugboat still in the wate
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-> SOLUTION: A tugboat can pull a boat 24 miles downstream in 2 hours. Going upstream, the tugboat can pull the same boat 16 miles in 2 hours. What is the speed of the tugboat still in the wate
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Question 1101210: A tugboat can pull a boat 24 miles downstream in 2 hours. Going upstream, the tugboat can pull the same boat 16 miles in 2 hours. What is the speed of the tugboat still in the 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 tugboat's speeds when traveling upstream and downstream related to its speed in sill water and the speed of the current? Answer by ikleyn(52786) (Show Source):
Let u be the speed of the tugboat in still water (in miles per hour).
Let v e the speed of the current.
Then the speed of the tugboat downstream is (u+v) miles per hour.
The speed of the tugboat upstream is (u-v) miles per hour.
From the other side, the speed downstream is = 12 mph. (it is the formula D =R*T, written in the form R = )
(Here R is the rate moving downstream.)
The speed upstream is = 8 hours. (Again, it is the formula D =R*T, written in the form R = )
(Here R is the rate moving upstream.)
So you have these two equations
u + v = 12, (1)
u - v = 8. (2).
Add the two equations. You will get
2u = 12+8 = 20 ====> u = = 10.
It is the speed of the tugboat in still water.
Now the speed of the current, from the equation (1), is v = 12-u = 12 - 10 = 2 mph.
Answer. The speed of the tugboat in still water is 10 mph.
The speed of the current is 2 mph.
