25*((1/(1*3))+(1/(3*5))+(1/(5*7))+...+(1/(23*25)))=how much.
25*((1/(1*3))+(1/(3*5))+(1/(5*7))+…+(1/(23*25)))=多少．
<gadget id="calculator">1 / 25</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">1 - (1/25)</gadget>
<output>24/25 = around 0.96</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(24/25) * (1/2)</gadget>
<output>12/25 = around 0.48</output>

<gadget id="calculator">25 * (12/25)</gadget>
<output>12</output>

<result>12</result>