# Rational Function Application Question

Cuisine123

## Homework Statement

A home security system costs $9/month in electricity costs (you may assume this is a fixed cost over the duration of the time involved in this question). A new security system costs$1500 to purchase and lasts for 8 years.

Determine a rational function that gives the annual cost of a security system as a function of the number of years you own the system. Using this function determine the average annual cost of the security system given above.

n/a

## The Attempt at a Solution

I got C(x)=(1500+108n)/n, where n is the number of years.
What would be the "average annual cost" of the security system given above?

## Answers and Replies

Homework Helper
Hi Cuisine123! got C(x)=(1500+108n)/n, where n is the number of years.
What would be the "average annual cost" of the security system given above?

That is the "average annual cost", isn't it? Cuisine123
Hi Cuisine123! That is the "average annual cost", isn't it? The questions says, "Determine a rational function that gives the annual cost of a security system as a function of the number of years you own the system. Using this function determine the average annual cost of the security system given above."

C(x)=(1500+108n)/n, where n is the number of years, would be the rational function that gives the annual cost of the security system.

What about the average annual cost of the security system given above ?
Would it be C(8)=(1500+108(8))/8?