and B are two identical cups. There is 1 cup of milk in cup A and (1/2) water in cup B. First pour (1/2) of the milk in cup A into cup B, then pour (1/3) of the mixed liquid of water and milk in cup B into cup A, and then pour the water and milk in cup A into cup A for the third time. Pour (1/4) of the mixed liquid of milk into Cup B, how much of the mixed liquid of water and milk in Cup A now accounts for Cup A.
甲、乙是两个完全一样的杯子．甲杯中有1杯牛奶，乙杯中有(1/2)水．先将甲杯中牛奶的(1/2)倒入乙杯，再将乙杯中水和牛奶混合液体的(1/3)倒入甲杯，第三次将这时甲杯中的水和牛奶混合液体的(1/4)倒入乙杯，现在甲杯中水和牛奶的混合液体占甲杯的多少．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">(1/3) - (1/4)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/2) + (1/12)</gadget>
<output>7/12 = around 0.583333</output>

<result>7/12 = around 0.583333</result>