The chicken farm originally raised 40,000 chickens in total. 12,800 pieces were sold for the first time, and 26,400 pieces were sold for the second time. How many chickens are there in the chicken farm?
养鸡场原来一共养了4万只鸡．第一次卖了1.28万只，第二次卖了2.64万只．养鸡场现在还养有多少为只鸡？
<gadget id="calculator">1.28 + 2.64</gadget>
<output>3.92</output>

<gadget id="calculator">4 - 3.92</gadget>
<output>0.08</output>

<result>0.08</result>