Question

For her cellular service, Dawn pays $32.00 a month, plus $0.75 for each minute over the allowed minutes in her plan. Write an algebraic expression that shows how much Dawn's bill will be for one month. Define your variable(s).
And Dawn received a bill for $47.00 last month. For how many minutes did she use her phone beyond the allowed minutes? Use your expression in the previous problem to solve this.

Answer 1

First part:

Since, Dawn pays $32.00 a month, plus $0.75 for each minute over the allowed minutes in her plan.

Let 'm' be the extra minutes used by Dawn over the allowed minutes in her plan.

So, Total bill = $\ 32 +(\ 0.75 \times m)$

Total bill of Dawn = $\ (32+0.75m)$

So, the expression which shows Dawn's bill for one month is:

$\ (32+0.75m)$

Second part:

Dawn received a bill for $47.00 last month.

Since, the expression for Dawn's bill for one month is:

Total bill =  $\ 32+\ 0.75m$

$\ 47 = \ 32+\ 0.75m$

$\ 47 - \ 32 = \ 0.75m$

$\ 15 = \ 0.75m$

$m = 20$

Therefore, Dawn used 20 minutes her phone beyond the allowed minutes.