Question 1063111
{{{ 1 - 7/12 = 5/12 }}}
Let {{{ t }}} = total number of people at concert
{{{ ( 5/12 )*t = 320 }}}
{{{ t = ( 12/5 )*320 }}}
{{{ t = 12*64 }}}
{{{ t = 768 }}}
There are 768 people at the concert