A census taker in a rural area went up to a farmhouse and knocked on the door. When a woman answered, he asked her the names and ages of her children.

She said: "Let's see now, there are the twins, Billy and Bobby, they're seventeen. And the twins, Seth and Beth, they're sixteen. And the twins, Benny and Jenny, they're fifteen."

"Wait a minute!" said the census taker. "Did you get twins every time?"

"Heck no," answered the woman. "There were hundred of times we didn't get nothin'."