Paul comes out of his room at the nursing home and remembers that to-day is his birthday. He is walking down the hall and Mary, (a crusty old broad) is sitting in a chair outside her room. Paul said "to-day is my birthday, can you guess how old I am"
Mary said "take your clothes off". Paul looking stuned said, "what has taking my clothes off got" he didn't get to finish the sentence because Mary cut in, "if you want me to guess your age, you take your clothes off". Paul did as he was told and soon was standing in the hall naked. Mary looked him up and down and finally said, "you are 84 years old". Paul was flabbergasted and said, " how can you tell my age by me standing here naked". Mary replied, "that was easy, you told me yesterday".