What is the sum of 4 20s and 5 10s?
4个20与5个10的和是多少．
<gadget id="calculator">4 * 20</gadget>
<output>80</output>

<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">80 + 50</gadget>
<output>130</output>

<result>130</result>