Question

Susana is with a mobile phone provider that charges $0.27 per minute plus a connection fee of $0.20. How much will she be charged for a

call that lasts b minutes?

Answer 1

The total monthly charge if one uses 769 minutes is $68.65

Explanation:

Example: If we are at x = 310, y = 45.50 and we use one more

minute, x goes up by 1, y increases by .05, putting us

at x = 311, y = 45.55. Thus, usage of 311 minutes

incurs a monthly cost of $45.55.

The y intercept is the point where x = 0.

That point on our equation is (0, 30)

This means that if zero minutes are used during the month,

the total charge for the month will be $30... the flat fee.

c) Find total monthly cost for using 769 minutes

y = .05x + 30

y = .05(769) + 30

y = 38.45 + 30

y = $68.65