What is the average of 1+2+3+4+5+6+7+8+9?
1+2+3+4+5+6+7+8+9的平均数是多少．
<gadget id="calculator">1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9</gadget>
<output>45</output>

<gadget id="calculator">45 / 9</gadget>
<output>5</output>

<result>5</result>