Math Riddles

These Math Riddles are based on math concepts and can be solved with a bit of math and logic. These fun riddles can surely give you a tough time.

The Mongolian Postal Service

The Mongolian Postal Service has a strict rule stating that items sent through the post must not be more than 1 meter long. Longer items must be sent by private carriers, and they are notorious for their expense, inefficiency, and high rate of loss of goods.

Boris was desperate to send his valuable and ancient flute safely through the post. Unfortunately, it was 1.4 meters long and could not be disassembled as it was one long hollow piece of ebony. Eventually he hit on a way to send it through the Mongolian Postal Service. What did Boris do?

Riddle Answer

Nine Lottery Balls

Ali and Zoe reach into a bag that they know contains nine lottery balls numbered 1 to 9. They each take one ball out to keep and they look at it secretly. Then, they make the following statements, in order:

Ali: I don’t know whose number is bigger.
Zoe: I don’t know whose number is bigger either.
Ali: I still don’t know whose number is bigger.
Zoe: Now I know that my number is bigger!

Assuming Ali and Zoe are perfect logicians, what is Zoe’s smallest possible number?

Riddle Answer