Calculation: (5/(2*3*4))+(7/(3*4*5))+…+(17/(8*9*10))+(19/(9*10*11) ).
计算：(5/(2*3*4))+(7/(3*4*5))+…+(17/(8*9*10))+(19/(9*10*11))．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 11</gadget>
<output>1/11 = around 0.090909</output>

<gadget id="calculator">(1/3) - (1/10) - (1/11)</gadget>
<output>47/330 = around 0.142424</output>

<gadget id="calculator">(1/2) + (47/330)</gadget>
<output>106/165 = around 0.642424</output>

<gadget id="calculator">(1/2) * (106/165)</gadget>
<output>53/165 = around 0.321212</output>

<gadget id="calculator">(1/3) - (1/11)</gadget>
<output>8/33 = around 0.242424</output>

<gadget id="calculator">(53/165) + (8/33)</gadget>
<output>31/55 = around 0.563636</output>

<result>31/55 = around 0.563636</result>