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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.

Question 8 options:

User Pedro Luz
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1 Answer

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The inequality is:
18 > 30 - 1.99x
because >18 is the end balance (y value), 30 is the original balance/starting value (y-intercept), and -1.99 is the amount the balance changes (slope) per every song download/day (x).
To solve the inequality, first subtract 30 from both sides, to get:
-12 > -1.99x
Then divide both sides by -1.99, but since you’re dividing by a negative, make sure to switch the inequality sign as well. This results in:
~6 < x
That means the gift card will still have a balance of more than 18 for a little more than 6 days.
This might be wrong so sorry if it is… my math and logic seems to make sense tho
User Amr Noman
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