How much is 20% of 40 equal to 80?
40的20%相当于80的多少．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) / 80</gadget>
<output>1/400 = around 0.0025</output>

<gadget id="calculator">40 * (1/400)</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>