I Used to Know That: Maths

I Used to Know That

by Chris Waring

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 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 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.

Genres: Nonfiction, Reference, Mathematics, Science

192 pages, Paperback

First published May 27, 2010

Reviews

[TheMadHatter · Rating 3 out of 5]

I need to start out by saying that I am not the target audience for this book so it was never going to be one of those things that changed my life. The reason I like to read these books is that I come across interesting or novel ways of explaining concepts that become invaluable in teaching practice.

This book actually had quite a few gems in it (and that is not surprising given that Chris is also a maths teacher). Nice way of explaining negative numbers (which is always a killer with juniors)and a really cool Venn diagram using historical figures and baldness (yes....baldness). I came across something that will definitely help in explaining like terms (which again kids seem to really struggle with when algebra is first introduced) and a really nice pictorial representation of Pythagoras' Theorem.

There were one or two issues I had and they just may be due to different terminology/teaching practices in different countries.

"Anything inside a bracket gets done first and any subtraction comes last"

I personally hate the BODMAS, BOMDAS, PEDMAS or BIDMAS (as Chris uses) as kids seem to think that division comes before multiplication and addition comes before subtraction. Trying to re-teach them that they are done at the same time (just left to right) is hard once they have the acronym firmly in their mind. I prefer:

B
O
DM (As it appears left to right)
AS (As it appears left to right)

Also, we don't refer to mode and median as measures of the average. Mean is another word for average and mean, mode and median are all measures of central tendency (or where the centre of the distribution tends to be). Again this may just be due to international differences. I worked as a statistician for many years and average was not a generic term for all three measures.

Lastly, the whole cylinder as a prism. Technically, it is not - but I have seen a few books now that gloss over that fact because it is simpler (and I am happy to go with that given that it is mathematicians who make the definitions).

Overall, this was a really well written book and a must for someone looking to refresh base level maths skills. Thanks Chris for some great teaching ideas :-)

[Ming · Rating 3 out of 5]

Great refresher, even though you may disagree with some of the calculation methods used (if you've been taught differently in school).

[Andrew · Rating 4 out of 5]

Quite a number of things that I recall from school. This is a worthwhile reference.

[Helena Kivistik · Rating 4 out of 5]

See raamat sattus mulle kätte valel ajal vales kohas aga osutus vajalikuks.

Leidsin emakeelse versiooni juhuslikult ja hakkasin lugema. Tegemist ei ole mitmekiudse teksti vaid lihtsameelse lõbusa mateemaatika käsitlusega. Raamat kordab üle kõik põhikooli matemaatilised teadmised ning seletab ka need lihtsa loogikaga lahti. Väga kasulik kui oled neljakümnendates pereelanik ning soovid teada kui palju pahtlit on vaja osta, et vannituba uuendada. Kriitikana toon välja mitmed (mitmed) kirjavead ja selle, et matemaatikat õpetatakse Ameerika matemaatika süsteemi järgi. Seega lugejale võib segaduseks jääda nii mõnigi meetod. Soovitan kõigile, kellel jäid põhikoolist lüngad sisse.

[John Naylor · Rating 3 out of 5]

A nice refresher for an adult to remember long forgotten mathematics from school. There was nothing I hadn't done at school (many years ago) here.
The best use of this would be for a parent to catch up to help their kids.
Probably not an essential book for anyone but one that could help some.

[Steve · Rating 3 out of 5]

I admit to skimming through it. Good to have on the shelf for reference and has got some interesting shortcuts for some mathematical operations. Probably most useful for parents or guardians who need to help young children with their homework.

[Charliiey Ann · Rating 3 out of 5]

3.75

[Damena Mccoy · Rating 5 out of 5]

This book is a great overview of all things math! It’s even broken down by topic and subtopics with an index to help for quick references.