If (1/2)△3=(1/2)*(1/3)*(1/4), (1/7)△2=(1/7)*(1/8), then please calculate (1/2)△4─(1/3)△4 result.
如果(1/2)△3=(1/2)*(1/3)*(1/4)，(1/7)△2=(1/7)*(1/8)，那么请计算(1/2)△4─(1/3)△4的结果．
<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 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/2) * (1/3) * (1/4) * (1/5)</gadget>
<output>1/120 = around 0.008333</output>

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

<gadget id="calculator">(1/3) * (1/4) * (1/5) * (1/6)</gadget>
<output>1/360 = around 0.002778</output>

<gadget id="calculator">(1/120) - (1/360)</gadget>
<output>1/180 = around 0.005556</output>

<result>1/180 = around 0.005556</result>