There are 8 numbers, the average of the first 3 numbers is 20, and the average of the last 5 numbers is 4, what is the average of these 8 digits?
有8个数，前3个数的平均数是20，后5个数的平均数是4，这8个位数的平均数是多少．
<gadget id="calculator">20 * 3</gadget>
<output>60</output>

<gadget id="calculator">4 * 5</gadget>
<output>20</output>

<gadget id="calculator">60 + 20</gadget>
<output>80</output>

<gadget id="calculator">80 / 8</gadget>
<output>10</output>

<result>10</result>