Question

tamikas cell phone plan gives her unlimited minutes for $15.50 per month. she is charged $0.08 for each text message, t. which equation models the total monthly cost, c, for the cell phone?
a c = 15.50t + 0.08
b c = 0.08t + 15.50
c c = 15.58t
d c = 15.42t

Explanation:

Step1: Identify fixed and variable costs

The fixed cost is $15.50 (monthly for minutes), and the variable cost is $0.08 per text (let \( r \) be number of texts).

Step2: Formulate total cost

Total cost \( C \) is fixed cost plus variable cost. Variable cost is \( 0.08r \), fixed is 15.50. So \( C = 0.08r + 15.50 \).

Answer:

B. \( C = 0.08r + 15.50 \)