Number Theory | Mathematics | Page 1

bold monolith Aug 21, 2023, 4:23 AM

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wild juncoBOT Aug 21, 2023, 4:23 AM

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lyric sable Aug 21, 2023, 1:40 PM

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you could just find the factors of 19,then find which 4 numbers satisfy the 2 equations

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I misread

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I thought ABCD was a product

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well yeah no

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the same method works there

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just by brute force you could find the answer

serene flame Aug 21, 2023, 2:21 PM

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You can write 19 | 10*ABC + D

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Then that means 19 | 20*ABC + 2*D and hence divides ABC + 2*D

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Using C+2*D = 7, this means 19 | AB7.

#Number Theory