If (5/9) of a number is 20, what is (3/10) of this number?
一个数的(5/9)是20，则这个数的(3/10)是多少．
<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">20 / (5/9)</gadget>
<output>36</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">36 * (3/10)</gadget>
<output>54/5 = around 10.8</output>

<result>54/5 = around 10.8</result>