(2008.12*18)-(2008.12*17)=how much.
(2008.12*18)-(2008.12*17)=多少．
<gadget id="calculator">2_008.12 * 18</gadget>
<output>36_146.16</output>

<gadget id="calculator">2_008.12 * 17</gadget>
<output>34_138.04</output>

<gadget id="calculator">36_146.16 - 34_138.04</gadget>
<output>2_008.12</output>

<result>2_008.12</result>