SOLUTION: what is the remainder when 3^31 is divided by 10?

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Question 357250: what is the remainder when 3^31 is divided by 10?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
3%5E1+=+3+mod10,
3%5E2+=+9+mod10,
3%5E3+=+7+mod10,
3%5E4+=+1+mod10.
3%5E31+=+3%5E28%2A3%5E3+=+%283%5E4%29%5E7%2A3%5E3++=1%2A7+mod10+=+7+mod+10.
Therefore the remainder is 7.