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More from Chalkdust
Once Upon A Prime
We review the third of this year's nominees for Book of the Year
A walk on the random side
Tanmay Kulkarni intentionally gets lost on the Tokyo subway
Review of Elastic Numbers
We have a go at the puzzles in Daniel Griller's new book
Why self-service machines give such awful change
Unexpected item in bagging areAAAARGGGHH here's 90p change in pennies
Problem solving 101
Never be stumped by a maths problem again, with this crash course from the ever-competent Stephen Muirhead
Victorian maths tricks with old money
Exploring mental arithmetic tricks in T. Martin's 1842 guide, 'Pounds, shillings and pence'