Phil asks his friend Stan when his birthday is. Stan replies that he was 32 the day before yesterday and next year he’ll be 35. When is his birthday and how is this possible?

There was a man who went to the mall where he bought 3 pairs of red socks and 3 pairs of white socks. Another man who had already bought 3 pairs of red socks and 3 pairs of white socks was on the way back to return his 6 pairs of socks. They were both blind.

As they were walking, they bumped into each other. All the socks scattered around the floor, but each pair remained held together by a rubber band. Nobody helped them pick the socks up, but in 3 minutes they both had 3 pairs of red, and 3 pairs of white. How is that possible if they are blind?

There are 10 identical bags of coins. Each bag contains 100 coins. In one bag the coins are silver, in the others gold. All the coins are identical. A gold coin weigh 10 grams and a silver coin weigh a gram less.

Given a regular measurement scale, how would you determine in one weighing which bag does not have the gold coins?

There are several books on a bookshelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?