SOLUTION: How do you determine the units digit of 3 to the 99th power???

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Question 89817: How do you determine the units digit of 3 to the 99th power???
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
3^1=3 ... 3^2=9 ... 3^3=27 ... 3^4=81 ... 3^5=243 (same units digit as 3^1)

the unit digits repeat in a pattern of four ... 99 divided by 4 is 24 with a remainder of 3

so the units digit for 3^99 is the third units digit in the pattern, which is 7