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## 'Power Mad!' printed from http://nrich.maths.org/

What is the impact of the units digits on the product of two or
more numbers?

e.g. what do you notice about the units digits in all the answers
to the following:

2 x 3

42 x 53

652 x 43

What can you say about the patterns of the units digits of powers
of 2, 3, 4, 5...?