SOLUTION: Sarah is interested in purchasing a new cell phone plan as her current cell phone plan doesn’t offer enough minutes. Her current calling plan is listed below. Using the concept of

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Question 501111: Sarah is interested in purchasing a new cell phone plan as her current cell phone plan doesn’t offer enough minutes. Her current calling plan is listed below. Using the concept of ratios and proportions, solve the problems below to determine the cost of the various options:
Sara’s current calling plan: 300 minutes per month for $39.99
If Sara can get 300 minutes for $39.99, how much will it cost her for 450 minutes?
If Sara can get 300 minutes for $39.99, how much will it cost her for 600 minutes?
If Sara can get 300 minutes for $39.99, how many will it cost her for 700 minutes?

Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
Sarah is interested in purchasing a new cell phone plan as her current cell phone plan doesn’t offer enough minutes. Her current calling plan is listed below. Using the concept of ratios and proportions, solve the problems below to determine the cost of the various options:
Sara’s current calling plan: 300 minutes per month for $39.99
If Sara can get 300 minutes for $39.99, how much will it cost her for 450 minutes?
300/3999 = 450/c (or 300:3999::450:c)
Cross multiply
300c = 3999*450
c = 3999*450/300
c = 5998.5 --> $59.99
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If Sara can get 300 minutes for $39.99, how much will it cost her for 600 minutes?
Do it like the 1st one.
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If Sara can get 300 minutes for $39.99, how many will it cost her for 700 minutes?
Do it like the 1st one.
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