The number A is 18, and (5/9) of the number B is 40. What percentage of the number A is the number B?
甲数是18，乙数的(5/9)是40，甲数是乙数的百分之几？
<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">40 / (5/9)</gadget>
<output>72</output>

<gadget id="calculator">18 / 72</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>