Sunland sells two different aluminum frames. Model $x$ sells for $$10$ and has variable costs of $$4\mathrm{.}00.$ Model $Y$ sells for $$14$ and has variable costs of $$9\mathrm{.}00.$ The sales mix of the three models is $x,30\%$ and $Y,70\%.$ Fixed costs are $$49,820.$ How many units of Model $x$ will Sunland sell at break$-$even? $($Round intermediate calculations to two decimal places $($e$.$g$.,5\mathrm{.}25),$ and final answers to nearest whole number $($e$.$g$.,2,510).)$