Leona is comparing the cost of cell phone bills between two different

companies. One option gives her unlimited data and texting for $40 a

month, but charges $0.25 per minute talking on the phone. The other plan

only charges $0.10 per minute talking on the phone, but charges $60 a

month for unlimited data and texting. How many minutes would she

spend talking on the phone for the plans to be the same price?

Answer: 133 minutes

Step-by-step explanation:

Hi, to answer this question we have to write an equation for the cost of each company:

Option one:

The cost is equal to the fixed fee (40) plus the product of the cost per minute talking on the phone (0.25) and the minutes spent talking in the phone in the month (m)

40 + 0.25 m

Option two:

The cost is equal to the fixed fee (60) plus the product of the cost per minute talking on the phone (0.10) and the minutes spent talking on the phone in the month (m)

60 + 0.10m

Since both costs must be equal:

40 + 0.25 m = 60 + 0.10m

Solving for m:

0.25m-0.10m = 60-40

0.15m = 20

m = 20/0.15

m = 133.34 minutes = 133 minutes (rounded)