((1/2)+(1/3)+…+(1/20))+((2/3)+…+(2/20))+…+((18/19)+(18/ 20))+(19/20)=how much.
((1/2)+(1/3)+…+(1/20))+((2/3)+…+(2/20))+…+((18/19)+(18/20))+(19/20)=多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + 19</gadget>
<output>20</output>

<gadget id="calculator">19 / 2</gadget>
<output>19/2 = around 9.5</output>

<gadget id="calculator">20 * (19/2)</gadget>
<output>190</output>

<gadget id="calculator">(1/2) * 190</gadget>
<output>95</output>

<result>95</result>