More from Chalkdust
An uncomfortable truth
Lucy Rycroft-Smith and Darren Macey unpick the legacy of some of the most ubiquitous names in statisticsTop Ten: Maths-themed days out
The definitive chart of the best day tripsTop Ten: Units of measurement
The definitive chart of the best unitsHow many cups does it take to make a sphere?
The Chalkdust team set you a challenge, for which the prize is a £25 Amazon voucher...Flexagon Templates
Print out and make a flexagonThe joys of the Jacobian
Robert Smith? tells us how his favourite matrix saves lives