Why is 6 afraid of 7?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

How can you make number one disappear by adding something to it?

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

What does this rebus mean?

O
N
C
E
TIME

You walk into a room where there are three primates held in their respective cages:
1) A lion who is eating the flesh of a goat.
2) An orangutan who is playing with blocks.
3) A donkey who is sitting idle.

Who is the most intelligent primate in the room?

What are the 50th, 63rd and 100th numbers in the sequence below?
4, 5, 8, 8, 9, 9, 12, 13, 13, 13, 17, 18, ...

Consider this: Arnold Schwarzenegger has a big one. Michael J. Fox has a small one. Prince doesn’t have one. The Pope has one but never uses it. Bill Clinton has one and uses it all the time. What is it?

How can a man go eight days without sleep?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?