According to the rules of the previous numbers, fill in the appropriate numbers in the brackets: (4/5), (2/5), (1/5), how much, (1/20).
根据前面几个数的规律，在括号里填上适当的数：(4/5)，(2/5)，(1/5)，多少，(1/20)．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">(1/5) * (1/2)</gadget>
<output>1/10 = around 0.1</output>

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