Question

Keith purchases a cell phone plan which includes a cell phone and cell phone service. He makes a deposit of $100 for the cell phone and then pays $45 per month for the cell phone service. Create an equation to model the total amount of money y in dollars keith spends on the cell phone and plan after x months

Answer 1

Explanation:

Let x be the number of months.

Given:

Initial deposit, c = $100

Monthly payments, m = $ 45

Total amount, t = initial deposit, c + monthly payments

Total amount, t = 100 + (45 × x)

The expression:

t = 100 + 45x

Answer 2

y = 100 + 45x

Explanation:

The cost structure of Keith expenditures can be referred to as mixed cost cost. A mixed cost is which a portion is fixed and the other variable.

The fixed portion does not depend on Keith accessing the phone service or not

While the variable cost depends upon the number of months for which he will access the service.

The total amount of expenditure he will spend is represented by the equation below:

y = 100 + 45x

y is the total expenditure on phone

100 is the fixed cost i.e the amount deposited

45 is the variable cost per month

x- is the number of month