Well, no-one knows exactly, but using stats you can make a good guess. This article tells you how and has an interactive life expectancy calculator. Do you dare to find out?

What's your strategy for love? Hold out for The One, or try and avoid the bad ones? How long should you wait before cutting your losses and settling down with whoever comes along next? **John Billingham** investigates and saves the national grid in the process.

According to one mathematician, god created the whole numbers, with everything else being the work of humanity. Why, then did god not equip us with a good way of writing them down? **Chris Hollings** reveals that our number system, much used but rarely praised, is in fact a work of genius and took millennia to evolve.

**Peter Markowich** is a mathematician who likes to take pictures. At first his two interests seemed completely separate to him, but then he realised that behind every picture there is a mathematical story to tell. *Plus* went to see him to find out more, and ended up with a pictorial introduction to partial differential equations.

Much criticism has been levelled at the US voting system, and with this being election year, we're bound to hear more of it. In this article **Steven J. Brams** proposes an alternative voting system that could help make things more democratic.

Computer-generated art is on the rise, and with it comes a further blurring of the boundaries between maths and art. **Lewis Dartnell** looks at some stunning examples.

Chuck Gill caught the space bug as a child when watching Alan Shepherd launch into space. Since then he's worked as a US Air Force navigator, a satellite operator, and in the US intelligence service. These days he's busy reducing carbon emissions and preparing London for the 2012 Olympics. *Plus* went to see him to find out more about his career.

This issue's teacher package brings together all *Plus* articles on group theory, exploring its applications and recent breakthroughs, and giving explicit definitions and examples of groups. It also has some handy links to related problems on our sister site NRICH.