Question

Tracy has a cell phone plan that provides 250 free minutes each month for a flat rate of $29. For any minutes over 250, Tracy is charged $0.35 per minute. Which of the following piecewise functions represents charges based on Tracy's cell phone plan?

Answer 1

`(29,x\leq 250)/(29+0.35(x-250)x\geq 250)`

Explanation:

Let x represent the total time spent calling and f(x) represent the charges.

Since Tracy is charged $29 for 250 free minutes, hence:

For x ≤ 250, f(x) = $29

Tracy is charged an extra $0.35 per minute for calls over 250 minutes, hence:

For x ≥ 250, f(x) = 29 + 0.35(x - 250)

Therefore this can be represented by the piecewise function:

f(x)=
`(29,x\leq 250)/(29+0.35(x-250)x\geq 250)`