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two digits

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More on the last 2 digits of a^k = N 2020-08-07
From Jay:
I've seen solution methods for finding the last 2 digits of a^k = N, where a and k are known. My question is:

What if the number N is known and the last 2 digits are, say, ...62. Is there a way to find, for any given a, the value of k which will result in a number where the last 2 digits are ...62? and if that is possible, then do the same for a number with the last n digits (say 7 or 53 or something)?

Answered by Harley Weston.
The last two digits of a phone number 2016-04-03
From Joshua:
I want to find the last two digits of a phone number whose first eight numbers of a ten digit phone numbers are known.
Answered by Penny Nom.
The last two digits 2006-07-22
From Sam:
You have answered this question already but you only answered to one digit.

What are the last TWO digits of:
3 to the power of 1994
7 to the power of 1994
3 to the power of 1994 + 7 to the power of 1994
7 to the power of 1994 - 3 to the power of 1994

Answered by Paul Betts and Penny Nom.
A palindrome question 2004-09-28
From Lilly:
12, 21, 13, and 31 are the only double-digit numbers whose squares are the palindromes of the squares of the palindromes of double-digit numbers. I was wondering why it works for these numbers, and if only these numbers work this way.
Answered by Chris Fisher and Penny Nom.



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