- #1
Burjam
- 52
- 1
Homework Statement
The cost of fuel to propel a boat through the water (in dollars per hour) is proportional to the cube of the speed. A certain ferry boat uses $100 worth of fuel per hour when cruising at 10 miles per hour. Apart from fuel, the cost of running this ferry (labor, maintenance, and so on) is $675 per hour. At what speed should it travel so as to minimize the cost per mile traveled?
Homework Equations
N/A
The Attempt at a Solution
I'm having trouble setting up functions to solve this problem. I could do it if I just had some solid functions to work with. The thing that's really getting me is the wording.
The problem states:
The cost of fuel to propel a boat through the water (in dollars per hour) is proportional to the cube of the speed. A certain ferry boat uses $100 worth of fuel per hour when cruising at 10 miles per hour.
Last time I checked, 10^3 is 1000. What's going on here?