Calculation: (5/(1*2*3))+(7/(2*3*4))+…+(19/(8*9*10))=how much.
计算：(5/(1*2*3))+(7/(2*3*4))+…+(19/(8*9*10))=多少．
<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">1 - (1/9)</gadget>
<output>8/9 = around 0.888889</output>

<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 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

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

<gadget id="calculator">(1/2) - (1/10)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/3) + (2/5)</gadget>
<output>16/15 = around 1.066667</output>

<gadget id="calculator">(1/2) * (16/15)</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">(8/9) + (8/15)</gadget>
<output>64/45 = around 1.422222</output>

<result>64/45 = around 1.422222</result>