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Home > Michael O'Mara Books > Maths & English > I Used to Know That

I Used to Know That


Extent: 192pages

Size: 198x129mm

Publication Date: 18/09/2014

Price: £5.99

ISBN: 9781782432555

Categories: Maths & English, Reference

About the Book

If memories of learning algebra bring you out in a cold sweat and thoughts of quadratic equations cause you feelings of fear and dread, I Used to Know That: Maths can help. A light-hearted and informative reminder of the things that we learnt in school but have since become relegated to the backs of our minds, this book will help you to brush up on your mental arithmetic, including percentages, averages and recurring decimals or work on your trigonometry skills, from Pythagoras' theorem to triangle areas and angles. A practical guide to turn to when an answer is eluding you, from helping a child with homework to calculating change or understanding statistics. I Used to Know That: Maths is a fun and accessible way to re-visit all those useful tips and maths tricks that you have forgotten from your school days.

About the Author

Chris Waring was born in London. After a degree in Mechanical Engineering at Imperial College London and a short yet disastrous career as a headhunter, he became a maths teacher. Since then he has taught small children and Oxbridge candidates and everybody in between. He has written I Used to Know That: Maths (2010) and From 0 to Infinity in 26 Centuries (2012) for Michael O'Mara Books. He lives in York.


  • 'Key concepts are defined and explained in a simple way in this very useful book', Parents in Touch
  • 'Highly recommended', The Bookbag