Modeling: Example 2

Modeling

Example 2

Suppose you have a gift card for $100 to an electronics store and want to spend it on CDs and DVDs. You want a special-edition DVD that costs $24.99, and the CDs you want are all on sale for $11.99 each. Assuming that you use only the gift card and you are going to buy the DVD, what is the maximum number of CDs you can buy?

Step 1. Define the variables.

Let c represent the number of CDs you can buy.

Step 2. Write an inequality to represent the situation and simplify.

Cost of DVD + Cost of each CDâ€¢(Number of CDs) ? Amount of Gift Card

24.99 + 11.99c ? 100.00

11.99c ? 75.01

c ? 6.26

Step 3. Answer the question.

6 is the maximum number of CDs that can be purchased using the gift card.

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