((1+3+5+...+17+19)/(2+4+6+...+18+20))=how much.
((1+3+5+…+17+19)/(2+4+6+…+18+20))=多少．
<gadget id="calculator">1 + 19</gadget>
<output>20</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">2 + 20</gadget>
<output>22</output>

<gadget id="calculator">22 * 5</gadget>
<output>110</output>

<gadget id="calculator">100 / 110</gadget>
<output>10/11 = around 0.909091</output>

<result>10/11 = around 0.909091</result>