Question

The phone company Ringular has a monthly cellular plan where a customer pays a flat monthly fee and then a certain amount of money per minute used on the phone. If a customer uses 300 minutes, the monthly cost will be $131. If the customer uses 990 minutes, the monthly cost will be $372.5. A) Find the slope and explain what it means

Answer 1

Answer:

The slope is $0.35/min and it gives the cost per minute of the phone used.

Step-by-step explanation:

We can model this situation with a linear equation of the form

$y =mx+b$

where $y$ is monthly cost, $x$ is the number of minutes, $b$ is the flat monthly fee, and $m$ is the slope of the equation, or in our case, the amount of money charged per minute.

The slope $m$ is

$m= \dfrac{\ 372.5-\ 131}{990min-300min}$

$m = \ 0.35/min$,

in other words, the phone company charges $0.5 per minute.

With the slope in hand, the linear equation becomes

$y =0.35x+b$,

and we can find the monthly fee $b$ from that fact that for 300 minutes the cost is $131:

$\ 131 = 0.35(300min) +b$

$b = \%26$.

Therefore,

$y = 0.35x+26$

where the slope if the equation give the cost per minute of the phone used.