A tax rate schedule is given in the table. If $x$ equals taxable income and $y$ equals the tax due, construct a function $y=f(x)$ for the tax schedule.

$\backslash$table$[[\backslash$table$[[$If taxable$],[$income is$],[$over$]],\backslash$table$[[$But not$],[$over$]],\backslash$table$[[$The tax is$],[$this$],[$amount$]],,\backslash$table$[[$Plus$],[$this $\%]],\backslash$table$[[$Of the$],[$excess$],[$over$]]],[0,7,500,0\mathrm{.}00,+,10\%,0],[7,500,30,600,750\mathrm{.}00,+,17\%,7,500],[30,600,74,200,4,677\mathrm{.}00,+,25\%,30,600],[74,200,,15,577\mathrm{.}00,+,31\%,74,200]]$

$f(x)=\{\begin{array}{ccc}0\mathrm{.}1x& if074,& 200\end{array}$