High Class Pig

A farmer decided one day that he wanted to breed his prize-winning hog. So, he put her in a cart and wheeled her to a farm five miles away, to breed with a high class pig. He paid $20 for the stud fee, and after they were done, brought his hog back to his farm.
The next day he went out to check and see if she was pregnant, but she was not. So, he put her back in the cart and wheeled her to a farm that was ten miles away, bred her with the pig there, who was said to be of higher class than the first, and paid his $50 stud fee. Then brought the hog back home.
But, when he checked the next day, she still was not pregnant! This time he wheeled her to a farm that was twenty miles away, and was the home of one of the best pigs in the county. He paid a $100 stud fee, and then wheeled his hog all the way back home and went to bed.
In the morning the farmer was just too exhausted to get out of bed and go see if his hog was finally pregnant, so he asked his wife to check for him. The wife came back and told her husband, “Well, she ain’t pregnant, but I found her in the cart and ready to go.”