Question 768964
Let {{{ n }}} = number of minutes used
The monthly charge, {{{ c }}} =  is
{{{ c = .09n + 5 }}}
given:
{{{ c = 27.23 }}}
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{{{ 27.23 = .09n + 5 }}}
{{{ .09n = 27.23 - 5 }}}
{{{ .09n = 22.23 }}}
{{{ n = 247 }}}
247 minutes of long distance calls were charged