The number A is equivalent to (8/9) of the number B. The number A is 72. What is the number B?
甲数相当于乙数的(8/9)，甲数是72，乙数是多少．
<gadget id="calculator">8 / 9</gadget>
<output>8/9 = around 0.888889</output>

<gadget id="calculator">72 / (8/9)</gadget>
<output>81</output>

<result>81</result>