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Find the smallest positive integer N such that
N &\equiv 2 \pmod{3}, \\
N &\equiv 2 \pmod{7}, \\
N &\equiv 2 \pmod{10}.

 Jul 7, 2024
 #1
avatar+1946 
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We have a system of equations to solve. We have

N2(mod3),N2(mod7),N2(mod10).

 

Now, let's note something really important. All 3 equations have a remainder of 2. 

Let's anakyze. 

N leaves a remainder of 2 when divided by 3, 7, and 10. 

Therefore, our answer is the LCM of 3, 7, and 10. 

 

This is because since they all leave the same remainder, the same number must be for all of them. 

Therefore, we have LCM[3,7,10]=210

 

Adding 2, we have 210+2=212

 

So our answer is 212. 

 

Thanks! :)

 Jul 7, 2024

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