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## 'Some Secret Codes' printed from http://nrich.maths.org/

Here is the alphabet:

a b c d e f g h i j k l m n o p q r s t u v w x y z

I have made a code that means we move $3$ places to the left to discover what the code stands for. But what will happen to

a b c ?

They pick up the letters left over at the end of the alphabet so that they become

You can think of the letters as if they were arranged on a wheel like this:

So can you work out what these codes stand for?

sdw - d - fdnh,

wkh - zhvw - zlqg - eorzv,

brx - duh - zrunlqj - kdug

Can you invent some messages of your own?

Can you create some different ways of coding?