5*how much=1.
5*多少=1．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) / 5</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">5 * (1/25)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>