question archive A cellular telephone company offers two plans
Subject:StatisticsPrice: Bought3
A cellular telephone company offers two plans. Plan A charges $20 a month for up to 75 minutes of airtime and $0.45 per minute above 75 minutes. Plan B charges $30 a month for up to 250 minutes
and $0.40 per minute above 250 minutes.
(a) Draw a graph of the Plan A charge against minutes used from 0 to 250 minutes.
(b) How many minutes a month must the user talk in order for Plan B to be less expensive than Plan A?