Insert a piece of data H into data 12, 15, 19, 58, 43, so that the median of the group of data is 20, then what is H
在数据12、15、19、58、43中插入一个数据H，使得该组数据的中位数是20，则H是多少
<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<gadget id="calculator">40 - 19</gadget>
<output>21</output>

<result>21</result>