(1/(1*2))+(1/(2*3))+(1/(3*4))+...+(1/(98*99))=how much.
(1/(1*2))+(1/(2*3))+(1/(3*4))+…+(1/(98*99))=多少．
<gadget id="calculator">1 / 99</gadget>
<output>1/99 = around 0.010101</output>

<gadget id="calculator">1 - (1/99)</gadget>
<output>98/99 = around 0.989899</output>

<result>98/99 = around 0.989899</result>