Question

A phone company offers two monthly charge plans. In Plan A, there is no monthly fee, but the customer pays cents per minute of use. In Plan B, the customer pays a monthly fee of and then an additional cents per minute of use. For what amounts of monthly phone use will Plan A cost more than Plan B? Use for the number of minutes of phone use in a month, and solve your inequality for .

Answer 1

For more than 180 minutes of phone use.

Step-by-step explanation:

Let m represent number of minutes of phone use in a month.

We have been given that in Plan A, there is no monthly fee, but the customer pays $0.06 per minute of use.

The cost of using m minutes in plan A would be
`0.06m`.

We are also told that in Plan B, the customer pays a monthly fee of $4.80 and then an additional $0.03 per minute of use.

The cost of using m minutes in plan B would be
`0.03m+4.80`.

To find the amounts of monthly phone when Plan A will cost more than Plan B, we will set cost of plane A greater than cost of plan B as:

`0.06m>0.03m+4.80`

Let us solve for m.

`0.06m-0.03m>0.03m-0.03m+4.80`

`0.03m>4.80`

`(0.03m)/(0.03)>(4.80)/(0.03)`

`m>180`

Therefore, Plan A will cost more than Plan B for more than 180 minutes of phone use.