If (5/6) of a number is 15, what is (7/9) of this number?
一个数的(5/6)是15，则这个数的(7/9)是多少．
<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">15 / (5/6)</gadget>
<output>18</output>

<gadget id="calculator">7 / 9</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">18 * (7/9)</gadget>
<output>14</output>

<result>14</result>