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38 votes
38 votes
Step Inequalities HW

Your cell phone plan costs $34.99 per month plus $0.12 for each text message you send or receive. You have at most $39 to spend on your cell phone bill. What is the maximum number of text messages that you can send or receive next month?

User Ivan Stoev
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1 Answer

19 votes
19 votes

Answer:

33

Explanation:

First, set up the equation. It's essentially a linear equation, except instead of our y= we have a set number that we cannot go above.

solve the inequality algebraically, as if it were a normal equation.

39 >= 0.12x+34.99

-34.99 -34.99

4.01 >= 0.12x

/0.12 /0.12

33.42 >= x

round the answer so it makes sense in the context of the equation. You can't have 0.42 text messages, so it makes the most sense to round down to 33.

User Rob Johnstone
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