Question

Customers of a phone company can choose between two service plans for long distance calls. The first plan has a $22 monthly fee and charges an additional $0.07 for each minute of calls. The second plan has an $8 monthly fee and charges an additional $0.12 for each minute of calls. For how many minutes of calls will the costs of the two plans be equal?

Answer 1

company a = 22 + 0.07m
company b = 8 + 0.12m

We are looking for the time when the prices are equal. i.e. the price of company a = the price of company b

company a = company b
22 + 0.07m = 8 + 0.12m
22 - 8 = 0.12m - 0.07m
14 = 0.05m
m = 14/0.05
m = 280

Therefore, the two companies will cost the same if you talk for 280 minutes