Question

Read the following prompt and type your response in the space provided.

Sarah has a $30 music gift card. Each day she uses it to buy a $1.99 song download. For how many days will the gift card have still have a balance of more than $18?

Write an inequality to solve the problem and then solve showing your work. Explain what the solution to the inequality means.

Answer 1

She will have a balance of more than $18 for up to 6 days

Explanation:

Start with $30.

Each day, x, subtract $1.99 from $30.

30 - 1.99x

The amount must be greater than $18.

30 - 1.99x > 18

Subtract 30 from both sides.

-1.99x > -12

Divide both sides by -1.99. Remember than when you multiply or divide both sides of an inequality by a negative number, the inequality sign changes direction.

-1.99x/(-1.99) < -12/(-1.99)

x < 6.03

The number of days must be less than 6.03. Since we deal with whole days, she will have a balance of more than $18 for up to 6 days.