HArd one to which I have not got an answer. But here is another tricky one A man is outside a hut which has no windows and one lightbulb inside. Outside are three switches. He must find which turns the light on and is only allowed to enter once to check. How does he proceed. Now for a joke: A young man is invited to a club by his grand farther and when he gets there hw discovfers that all the men know jokes so well that they just say the number of the joke. ONe old man: 26 THe whole house laughs Another old man: 56 more laughs Finally the young man picks up his courage and says: 18 total silence Young man: What? Isn't the joke funny? An old man: It's not the joke! Its the way you say it!