Question

A cell phone company charges its customers $40 each month for owning a cell phone plan and $0.25 for

each minute the customer talks on the phone. These costs are modeled by the following equation:
C=25m +40, where Crepresents the total cost of the bill and m represents the number of minutes the
customer talked on the phone that month. Given this equation, how many minutes would the customer
have to talk on the phone for their monthly bill to be $84.25? (Hint: plug in 84.25 for the total cost, C, and
solve for the unknown, m).

Answer 1

The customer would have 177 minutes to talk on the phone for their monthly bill to be 84.25

Explanation:

Point of correction it's not C=25m +40 but it is

C=0.25m +40

Where,

• C = $84.25

➟ 84.25 = 0.25m + 40

Let's solve your equation step-by-step.

84.25=0.25m+40

Step 1: Flip the equation.

0.25m+40=84.25

Step 2: Subtract 40 from both sides.

0.25m+40−40=84.25−40

0.25m=44.25

Step 3: Divide both sides by 0.25.

0.25m/0.25 = 44.25/0.25

m=177

∴ The customer would have 177 minutes to talk on the phone for their monthly bill to be 84.25