Equations and Inequalities

Question

Zach pays a monthly fee of $3.95 plus $0.10 per minute for long distance calls. Write an equation for the phone bill p in terms of number of minutes m. Then solve to write an ordered pair (m,p) that shows the phone bill for 120 minutes.

Answer 1

The phone bill (pp) can be represented by the equation:

p=3.95+0.10m,p=3.95+0.10m, where mm is the number of minutes for the long distance calls. The $3.95 represents the fixed monthly fee, and the 0.10m0.10m represents the additional cost based on the number of minutes (mm).

To find the phone bill for 120 minutes, we substitute m=120m=120 into the equation:

p=3.95+0.10⋅120=3.95+12=15.95.p=3.95+0.10⋅120=3.95+12=15.95.

So, the ordered pair (m,pm,p) that shows the phone bill for 120 minutes is (120, $15.95). This means that for 120 minutes of long distance calls, Zach's phone bill would be $15.95.