Add half of a number to 8 to get 19, what is this number?
一个数的一半加上8得19，这个数是多少？
<gadget id="calculator">19 - 8</gadget>
<output>11</output>

<gadget id="calculator">11 / 0.5</gadget>
<output>22</output>

<result>22</result>