Logic Riddles

Question: In 1940, a correspondent proposed the following question:

A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?

Question: I'm number three.
But I'm not a number.
I'm hot and cold at the same moment but not at the same time.
I'm number three.
But I'm not a number.

Who or what am I?

Question: Mr. Smith has two children. If the older child is a boy, what are the odds that the other child is also a boy?

Question: You are surrounded by a 100 foot wide and 100 foot deep moat. You have a 40 foot tall ladder, matches, a gallon of water, and as much rope as you need.

How can you get across the moat?

Question: In a town their is a barber who cuts everybody in the town's hair. But nobody in the town cuts their own hair. Yet the barbers always has beautifully kept and full hair.

Who cuts the barber's hair?