### Squash

If the score is 8-8 do I have more chance of winning if the winner is the first to reach 9 points or the first to reach 10 points?

### A Method of Defining Coefficients in the Equations of Chemical Reactions

A simple method of defining the coefficients in the equations of chemical reactions with the help of a system of linear algebraic equations.

### Playing Squash

Playing squash involves lots of mathematics. This article explores the mathematics of a squash match and how a knowledge of probability could influence the choices you make.

# Stonehenge

##### Stage: 5 Challenge Level:

In times gone by men moved very heavy stones by using logs as rollers. Assuming all the logs have the same radius and that the logs roll and do not slide explain why the stone moves in the direction the men push it twice as fast as the logs. (Try a similar experiment yourself, for example with some pencils and a heavy book, and you will find you leave the 'logs' behind at the back and have to move them into position in front of the 'stone'.)