Question 1132577
Let {{{ t }}} = number of minutes used per month
when the plans become equal
Let {{{ c }}} = cost of plans in cents
1st plan:
(1) {{{ c = 18t }}}
2nd plan:
(2) {{{ c = 8t + 4995 }}}
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Plug (1) into (2)
(2) {{{ 18t = 8t + 4995 }}}
(2) {{{ 10t = 4995 }}}
(2) {{{ t = 499.5 }}} min