SOLUTION: one phone company charges 99 cents per call, plus5 cents per minute. A second phone company charges 8 cents per minute with no connection fee. what length phone calls are cheaper w

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Question 394512: one phone company charges 99 cents per call, plus5 cents per minute. A second phone company charges 8 cents per minute with no connection fee. what length phone calls are cheaper with the first phone company?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Let m = # minutes , which I will treat as a CONTINUOUS variable (rather than discrete).
Then we want
0.99 + 0.05m < 0.08m
==> 0.99 < 0.03m
==> 33 < m
Hence for any number of minutes greater than 33 minutes, the 1st phone company is cheaper.
( Treating m as a discrete variable is actually anti-consumer, because if you spent for example, 25.01 minutes of phone call, then you get charged m = 26 minutes. Would you like that?)