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that day, a friends of mine asked me to find out the last digit of 3^999. i knew that i have to find out 3^999 mod 10. but i saw that

3^3 mod 10

= 3^7 mod 10

= 3^11 mod 10 =7

= 3^15 mod 10 =7

.

.

.

=3^999 mod 10 = 7

but i was wondering what if i want to find the last two digits of 3^999. how can i do that?

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# Last digits of 3^999

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