Calculation: (1-(1/2))(1-(1/3))(1-(1/4))(1-(1/5))(1-(1/6))(1- (1/7))(1-(1/8))=how much.
计算：(1-(1/2))(1-(1/3))(1-(1/4))(1-(1/5))(1-(1/6))(1-(1/7))(1-(1/8))=多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">6 / 7</gadget>
<output>6/7 = around 0.857143</output>

<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">(1/2) * (2/3) * (3/4) * (4/5) * (5/6) * (6/7) * (7/8)</gadget>
<output>1/8 = around 0.125</output>

<result>1/8 = around 0.125</result>