A phone company charges for service according to the formula C(n) = 27+0.2n, where n is the number of minutes talked and C(n) is the monthly charge, in dollars. Find the rate of change: Initial value:

Answer:

Monthly charge(C_n):

• C_n = 27+0.2n, where n = # minutes.

Rate of change of 0.2 implies that the company charges $0.2 per 1 minute call.

In other words, monthly charge increases by $0.2 in every minute you use it for a phone call.

The y -intercept of 27 implies that the company charges a fixed monthly amount of $27. That is, when you subscribe to their service, even you have not yet used it for a phone call, you have an initial charge of $27. This inceases then by $0.2 as discussed above.