Question 1095098
Let {{{ S }}} = the sum of the scores of the 12 students
{{{ 80 = S/12 }}}
{{{ S = 960 }}}
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The smallest possible score of the other students ( not A's )
happens when each of the A students gets 100%
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{{{ 4*100 = 400 }}}
and
{{{ 960 - 400 = 560 }}}
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So, there are {{{ 12 - 4 = 8 }}} students who didn't get A's and
Let {{{ x }}} = their minimum possible mean % score
{{{ x = 560 / 8 }}}
{{{ x = 70 }}}
70% is the answer
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