I’ve got a new favourite number – 243.
Why is it my favourite? It’s not because it’s 3 to the power of 5, although that does make it special.
To find out why 243 is my new favourite number, divide 1 by 243: 1 ÷ 243
OK, to save you doing the maths, the answer to 1 ÷ 243 is:
0.004115226337448559 …
which I think is pretty cool.
Now, I’d like to say I discovered this little gem for myself, but I’d be lying. I stumbled across this little snippet whilst reading:
Surely You’re Joking Mr Feynman: Adventures of a Curious Character as Told to Ralph Leighton
Richard Feynman was a great physicist, but this book is not just about physics, its a fascinating and amusing tale of an extraordinary life. You might enjoy reading it, too.
Teaching Tips
How could you use this in a maths lesson?
You could just as your pupils to divide 1 by 243, but that’s quite hard.
But introduce them to division by factors – so to divide by 243, you can split 243 into factors and divide by those.
As 243 = 35 you could divide 1 by 3, then divide that answer by 3, then divide that answer by 3, then divide that answer by 3 and then divide that answer by 3 but it would be much quicker – and much more interesting – to do 1 divided by 9, then divide that answer by 9, then divide that answer by 3 (as 243 = 9 x 9 x s)
Go on, grab a scrap of paper and have a go yourself!