Logic Riddles

Question: 7 frogs are sitting on a log. 1 of them decides to jump off of the log. At this moment how many frogs are on the log?

Question: A man walks into a completely dark room. There is a box on a table at the other end of the room and immediately the man knows one of the contents of the box. He cannot smell, see, or hear it.

How does he immediately know what is inside?

Question: You have a cube made of 10 x 10 x 10 smaller cubes, for a total of 1000 smaller cubes. If you take off 1 layer of cubes, how many remain?

Question: You have two buckets: one with only white marbles and one with only black marbles. The two buckets have the same number of marbles.

How can you rearrange the marbles to maximize your chances of grabbing a white marble from each?

Question: What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.