Question 675617
Let her sister's age =  {{{ x }}}
{{{ x + 3 }}} = Susan's age
given:
{{{ x + x + 3 = 33 }}}
{{{ 2x + 3 = 33 }}}
{{{ 2x = 30 }}}
{{{ x = 15 }}}
and
{{{ x + 3 = 18 }}}
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Susan's age is 18
Her Sister's age is 15