SOLUTION: What is the units digits of 13^1972?

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Question 1004790: What is the units digits of 13^1972?
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
If you do the first five powers, you will see that the units digits cycles...
13
169
2187
ends in 1
ends in 3
etc...every four powers, it ends in 3,9,7,1...
since 1972 is divisible by four evenly, 13^1972 must end in a 1.