Question 1141263
Let {{{ C }}} = the monthly cost of a plan
Let {{{ t }}} = the number of monthly minutes of calls
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(1) {{{ C = 10 + .16t }}}
(2) {{{ C = 27 + .12t }}}
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Make the costs of the plans equal
{{{ 10 + .16t = 27 + .12t }}}
{{{ .04t = 17 }}}
{{{ t = 425 }}}
For 425 min of calls the two plans will be equal
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Check:
(1) {{{ C = 10 + .16*425 }}}
(1) {{{ C = 10 + 68 }}}
(1) {{{ C = 78 }}}
and
(2) {{{ C = 27 + .12*425 }}}
(2) {{{ C = 27 + 51 }}}
(2) {{{ C = 78 }}}
OK