2. The third customer bought the remaining half of the duck eggs, and there are still 6 duck eggs in the basket, indicating that there is 12 in the box at this time. After buying 12/2=6, there is still 6.

3. After the second customer came to buy more than half of the leftover duck eggs, there was 12 in the box. With 12+2= 14, we can know that there is 14*2=28 left in the box.

The first customer came and bought half of the duck eggs. After three eggs are missing, there are 28 in the basket, and there are 25*2=50 left in the box of 28-3=25.