Chinese Remainder Theorem: How Can It Help Solve Modulo Residue Problems?

saadsarfraz
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Chinese remainder theorem, urgent!

Homework Statement



This is an attempt to make the Chinese Remainder Theorem more concrete.
Let m = 206 and n = 125. You may use the fact that 89n - 54m = 1.

(a) What does the Chinese Remainder Theorem have to say about pairs
of residues modulo 206 and 125? How do you know that it applies?

(b) Find residues x and y modulo mn = 25,750 where
x = 1 (mod m); x = 0 (mod n);
y = 0 (mod m); y = 1 (mod n):

(c) Find a residue z modulo 25,750 where
z = 10 (mod m); z = 24 (mod n):

Homework Equations



see above

The Attempt at a Solution



for part a) CRT says that there is a unique N modulo mn such that N=a mod m and N=b mod n. I don't know what "How do you know that it applies means". The problem set is due in a couple of hours. I would be very grateful for any help.
 
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I think for part b) x=413=1 mod 206 and y=412=0 mod 206 makes sense. but i don't know if x and y have to be the same for the two mods m and n.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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