Solution:

3

Explanation:
If I had 4 eggs -- Its just imagination.
A thief gives me 3 -- I go three eggs.
My farm rooster lays 5 eggs -- A Rooster can't lay eggs.

Solution:

There are 7 people.

Solution:

In a clock.

Solution:

The girl sitting on your lap.

Solution:

The boy in the center. He doesn't have any shadow.

Solution:

No, because it will be night again in 72 hours, and there can be no sun in the sky.

Solution:

It can be done as shown in the picture below.

Solution:

10 + 10 = 20
11 + 11 = 22 or we can say 20 too.

Solution:

123 - 45 - 67 + 89

Solution:

Turn it upside down as shown.