the speed of the current in a river is 6 mph a ferry operator who works that part of the river is looking to buy a new boat for his business everyday his route takes him 22.5 miles against the current and back to his deck and he needs this trip in a total of 9 hours he has a boat in mind but he can only test it on a lake where there in no current how fast must the boat go on the lake in order for it to serve the ferry operators needs?

i understand the problem i just need help writing it out. ty!

4 answers

time = distance/speed
If his boat has speed s, then the time upstream + the time downstream adds up to 9 hours, so

22.5/(s-6) + 22.5/(s+6) = 9
is this math?
yes, algebra is math.
thank you !!:)