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UKMT Grey Kangaroo, 2020

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

How many four-digit numbers $N$ are there, such that half of the number $N$ is divisible by 2, a third of $N$ is divisible by 3 and a fifth of $N$ is divisible by 5?

(A) $1$ (B) $7$ (C) $9$ (D) $10$ (E) $11$

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