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• Company G charges a flat rate of $5 plus $5 for every 30 minutes used. Company X charges no flat rate, but does charge $10 for every 30 minutes used.
• Graphs 1 and 2 correspond to this relationship.
• Mr. Stephens is trying to decide which cell phone company to choose. He decides that if he uses exactly 30 minutes, then both companies would charge the same amount.
• Are Mr. Stephens's conclusions reasonable; why or why not?

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Check Your Answers

Yes, Mr. Stephens' conclusion is reasonable. If x = number of 30 minutes increments, then
Company G = 5x + 5 = 5(1) + 5 = 10
Company X = 10x = 10(1) = 10
So both companies would charge $10 for 30 minutes used.

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