I’m tall when I’m young, and I’m short when I’m old. What am I?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

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

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

What is full of holes but still holds water?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

If 21x = 79x, what is the value of x?