Calculation: (1/(2*3))+(1/(3*4))+(1/(4*5))+...+(1/(98*99))=how much.
计算：(1/(2*3))+(1/(3*4))+(1/(4*5))+…+(1/(98*99))=多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 99</gadget>
<output>1/99 = around 0.010101</output>

<gadget id="calculator">(1/2) - (1/99)</gadget>
<output>97/198 = around 0.489899</output>

<result>97/198 = around 0.489899</result>