Question 846673
Let {{{ d }}} = the number of dolls
{{{ (1/3)*18 + (1/6)*18 + d = 18 }}}
{{{ 6 + 3 + d = 18 }}}
{{{ d = 18 - 9 }}}
{{{ d = 9 }}}
She has 9 dolls
check:
{{{ (1/3)*18 + (1/6)*18 + 9 = 18 }}}
{{{ (1/3)*18 + (1/6)*18 = 9 }}}
Multiply both sides by {{{ 6 }}}
{{{ 36 + 18 = 54 }}}
{{{ 54 = 54 }}}
OK