# Puzzles

﻿We are all about fun mathematics. Try these two puzzles. Send us your thoughts if you like via an email to navajomath@gmail.com.
Check back for more puzzles!

1. (From our friend, @jamestanton):The number 21200 is self-describing: it has 2 zeros,1 one, 2 twos, 0 threes, and 0 fours. How many 5-digits numbers almost like this? How many are correct in 4 of the 5 digits?
2. Can you plant exactly seven trees, so that there are exactly six rows, each containing exactly three trees?
3. Is it possible to slice a cube with a straight plane to get a pentagon? Is it possible to slice a cube with a straight plane to get a regular pentagon? Is it possible to slice a cube with a straight plane to get a regular hexagon?
4. The number $$2015!$$ is a really large number. It is equal to $$1 \times 2 \times 3 \times \cdots \times 2014 \times 2015$$ How many zeros does it end with?

We like people to view the material on our website. However, we can’t resist pointing out a couple of nice puzzle sites with many good ones. Check out https://krazydad.com/ and https://braineaser.com/.