A phone company offers two monthly charge plans. In Plan A, there is no monthly fee, but the custome

A phone company offers two monthly charge plans. In Plan A, there is no monthly fee, but the customer pays 8 cents per minute of use. In Plan B, the customer pays a monthly fee of $1.50 and then an additional 7 cents per minute of use.

For what amounts of monthly phone use will Plan A cost more than Plan B?

Set up the cost equations for each plan. The cost equation for the phone plans is as follows:
Cost = Cost Per Minute * Minutes + Monthly Fee

Calculate the cost of Plan A:
Cost for A = 0.08m + 0. <-- Since there's no monthly fee

Calculate the cost of Plan B:
Cost for B = 0.07m + 1.50

The problem asks for what amounts of monthly phone use will Plan A be more than Plan B. So we set up an inequality:
0.08m > 0.07m + 1.50

Typing this inequality into our search engine, we get:
m > 150

This means Plan A costs more when you use more than 150 minutes per month.