# Homework Help: Find the cost function C(x)

1. Dec 1, 2004

### ziddy83

I was wondering if anyone can help me on this problem...

A truck burns fuel at the rate of G(x) gallons per mile. Where

$$G(x) = \frac {1} {32} \left(\frac {64}{x} + \frac {x}{50} \right)$$

a. Find the cost function C(x) if the truck takes a 400 mile trip. Assume that the cost of fuel is \$1.60 per gallon.

b. What is the speed that will produce minimum cost on this trip?

So....if anyone can help me with this...Please..please do so, I would be very very appreciative. Thanks

2. Dec 1, 2004

### HallsofIvy

What does x represent?????

At first I thought it was the distance which makes (a) easy but then (b) makes no sense. Is x the speed? No, that way (a) makes no sense!

3. Dec 1, 2004

### ziddy83

oh sorry....x represents miles per hour

4. Dec 4, 2004

### ziddy83

How can i determine the cost function? Anyone?

5. Dec 5, 2004

### ziddy83

nobody can help?