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UKMT Junior Mathematical Challenge, 2018

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

A drawer contains ten identical yellow socks, eight identical blue socks and four identical pink socks. Amrita picks socks from the drawer without looking. What is the smallest number of socks she must pick to be sure that she has at least two pairs of matching socks?

(A) $5$ (B) $6$ (C) $8$ (D) $11$ (E) $13$

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