Answer:
Chickens lay eggs like this: Female Chicken meets male chicken. The two chickens express their love and an egg is "planted"in the female chickens bum. Later, she tries to poo, but instead comes out an egg.
But seriously, folks: Female chickens (hens) lay eggs, regardless of the presence of a male chicken (rooster). If the avian love making is successful, the egg is fertilized and a chick can develop. Fertilized or not, all eggs are laid the same, through the oviduct. A hen will try to incubate all her eggs--not just the fertilized ones.