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## 'Unit Differences' printed from http://nrich.maths.org/

This challenge is about finding the difference between numbers which have the same tens digit.

Here are two examples where I’ve decided to use numbers which have two tens:

The number above is always the difference between the two beneath it.

Can you find different pairs of numbers with a difference of 1 or 2 or 3 or 4 ... and so on?

Can you find more than one way of doing it?