SOLUTION: The speed of a stream is 5 mph. A boat travels 7 miles upstream in the same time it takes to travel 17 miles downstream. What is the speed of the boat in still​ water?
Question 1127384: The speed of a stream is 5 mph. A boat travels 7 miles upstream in the same time it takes to travel 17 miles downstream. What is the speed of the boat in still water? Found 2 solutions by ikleyn, 4198181:Answer by ikleyn(52824) (Show Source): You can put this solution on YOUR website! .
The time equation is
= .
7*(x+5) = 17*(x-5)
7x +35 = 17x - 85
35 + 85 = 17x - 7x
120 = 10x
x = 120/10 = 12.
Answer. The speed of the boat in still water is 12 miles per hour.
Solved.
Answer by 4198181(13) (Show Source): You can put this solution on YOUR website! Obviously the boat can move itself so to find how fast it moves in still water we would do 17-5 because 5 miles is how far it can move without propelling itself and 17 miles is how far the boat can propel itself and the river will move it. 17-5 is 12 so the speed of the boat in still water is 12mph