There are 7 numbers arranged in a row, their average is 27, the average of the first 4 numbers is 23, and the average of the last 4 numbers is 34, what is their median.
有7个数排成一列，它们的平均数是27，前4个数的平均数是23，后4个数的平均数是34，它们的中位数是多少．
<gadget id="calculator">23 * 4</gadget>
<output>92</output>

<gadget id="calculator">34 * 4</gadget>
<output>136</output>

<gadget id="calculator">92 + 136</gadget>
<output>228</output>

<gadget id="calculator">27 * 7</gadget>
<output>189</output>

<gadget id="calculator">228 - 189</gadget>
<output>39</output>

<result>39</result>