The supervisor of a school was trying to prove that children are lacking in observation.
To the children he said, "Now, children, tell me a number to put on the board."
Some child said, "Thirty-six." The supervisor wrote sixty-three.
He asked for another number, and seventy-six was given. He wrote sixty-seven.
When a third number was asked, a child who apparently had paid no attention called out:
"Theventy-theven. Change that you thucker!"