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UKMT Grey Kangaroo, 2016

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

Two pieces of rope have lengths $1$ m and $2$ m. Alex cuts the pieces into several parts. All the parts have the same length. Which of the following could not be the total number of parts he obtains?

(A) $6$ (B) $8$ (C) $9$ (D) $12$ (E) $15$

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