Four times a number is (20/21), what is this number?
一个数的4倍是(20/21)，这个数是多少？
<gadget id="calculator">20 / 21</gadget>
<output>20/21 = around 0.952381</output>

<gadget id="calculator">(20/21) / 4</gadget>
<output>5/21 = around 0.238095</output>

<result>5/21 = around 0.238095</result>