[IntroNumTheory] Determining the remainder by using congruence

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The discussion focuses on using congruences to determine the remainder of 453 raised to the power of 234 modulo 100. The initial steps involve simplifying the problem by expressing 453 as congruent to 53 modulo 100 and then further reducing it to 9 modulo 100. The user encounters difficulty in calculating 3 raised to the power of 234 modulo 100. A suggestion is made to use a calculator or spreadsheet to find lower powers of 3 until a manageable result appears. The conversation emphasizes the application of congruence properties to simplify calculations in number theory.
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I need to use the congruence to solve this question. My strategy is to write the question as a congruence and then simplify the congruence so that I can apply Congruence to remainder to get the remainder. My work is as follows:
We know that
##453\equiv 53 (mod\, 100)##
Thus,
##453^{234}\equiv 53^{234} (mod\, 100)## by Congruence Power.
Also since
##53^2\equiv 9 (mod\, 100)##,
##53^234\equiv 9^{117} (mod\, 100)##.
So by the transitivity property, we have
##453^{234}\equiv 3^{234} (mod\, 100)##
But I am stuck here. Can someone help me out, please?
 
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Why not do powers of 3 on a calculator (or better on a spreadsheet) until something low modulo 100 appears?
 

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