A's number is B's (5/9), B's number is 18, what is A's number?
甲数是乙数的(5/9)，乙数是18，甲数数多少．
<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">18 * (5/9)</gadget>
<output>10</output>

<result>10</result>