A piece of cake was cut into 9 pieces on average, mother ate 3 pieces, Xiaoming ate 2 pieces, father finished the rest, and father ate ((())/(())) of the piece of cake.
一张饼平均切成9块，妈妈吃了3块，小明吃了2块，剩下的爸爸吃完，爸爸吃了张饼的((())/(()))．
<gadget id="calculator">9 - 3 - 2</gadget>
<output>4</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<result>4/9 = around 0.444444</result>