Simple calculation: 20*0.8+0.8+0.8*8.4.
简便计算：20*0.8+0.8+0.8*8.4．
<gadget id="calculator">20 * 0.8</gadget>
<output>16</output>

<gadget id="calculator">0.8 * 8.4</gadget>
<output>6.72</output>

<gadget id="calculator">16 + 0.8 + 6.72</gadget>
<output>23.52</output>

<result>23.52</result>