SOLUTION: Three friends each have different monthly payment plans for sending text messages.
 Naomi pays a flat fee of $30 for an unlimited number of text messages.
 Tina p
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-> SOLUTION: Three friends each have different monthly payment plans for sending text messages.
 Naomi pays a flat fee of $30 for an unlimited number of text messages.
 Tina p
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Question 1026520: Three friends each have different monthly payment plans for sending text messages.
Naomi pays a flat fee of $30 for an unlimited number of text messages.
Tina pays a base fee of $6.00 plus $0.10 per text message.
Chris pays a base fee plus $0.05 per text message. Last month, he paid $18.00 for 100 text
messages.
Naomi researched how much she would have to pay if she switched to Tina or Chris's plan. She
decided that her plan is the least expensive based on the number of text messages she uses each
month. What is the minimum number of text messages Naomi must use each month for her plan to be
the least expensive? Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! Let = the cost of a plan
Let = the number of text messages
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First find Chris's base fee:
Let her base fee =
So, Chris's equation for her plan is:
Naomi's equation is:
Tina's equation is:
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Find the smallest so that
is smallest for Naomi
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For what , does Tina pay same as Naomi?
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For what , does Chris pay same as Naomi?
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341 text messages is the least she can send and
be less expensive
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check:
Chris's equation for her plan is:
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Naomi:
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Tina's equation is:
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If 341 texts are sent:
Chris:
Naomi:
Tina:
Naomi is less expensive
