Four times the difference of a number minus 5 is 12. Find this number.
某数减去5的差的4倍是12．求这个数．
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">20 + 12</gadget>
<output>32</output>

<gadget id="calculator">32 / 4</gadget>
<output>8</output>

<result>8</result>