Clever calculation: (1/(2*3*4))+(1/(3*4*5))+(1/(4*5*6))+…+(1/(98*99*100 )).
巧算：(1/(2*3*4))+(1/(3*4*5))+(1/(4*5*6))+…+(1/(98*99*100))．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">99 * 100</gadget>
<output>9_900</output>

<gadget id="calculator">1 / 9_900</gadget>
<output>1/9_900 = around 0.000101</output>

<gadget id="calculator">(1/6) - (1/9_900)</gadget>
<output>1_649/9_900 = around 0.166566</output>

<gadget id="calculator">(1/2) * (1_649/9_900)</gadget>
<output>1_649/19_800 = around 0.083283</output>

<result>1_649/19_800 = around 0.083283</result>