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by sujaysolanki » Mon Dec 10, 2007 10:03 am
3^4 +3^4 + 3^3 = 1+1+7 = 9/5 = 4
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by hemanth28 » Mon Dec 10, 2007 10:07 am
units digits of power of 3 are
3,9,7,1,3,9,7,1.....
so units digit is repetative in multiples of 4

so for 3^(8n+3) ,units digit =(units digit of 3^(8n)) * (units digit of 3^3)

=7
add 2 and divide by 5 gives reminder of 4.
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by NSNguyen » Tue Dec 11, 2007 6:47 am
Thanks! :D
Please share your idea and your reasoning :D
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