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Number TheoryChallengeThe Chinese Remainder Theorem

The Chinese Remainder Theorem · Challenge problem

For how many pairs (a,b)(a, b) with 0≤a<120 \le a < 12 and 0≤b<180 \le b < 18 does the system x≡a(mod12)x \equiv a \pmod{12}, x≡b(mod18)x \equiv b \pmod{18} have a solution?