Question 1064412
To get 60% as a fraction, divide by {{{ 100 }}}
{{{ 60/100 = 6/10 }}}
and
{{{ 6/10 = 3/5 }}}
She ate 3/5 of the cake
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To get the percent of the cake left, subtract
{{{ 60 }}} from {{{ 100 }}} 
Note that 100% means the whole cake
{{{ 100 - 60 = 40 }}}
40% of the cake is left