UKMT Pink Kangaroo, 2022

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Veronica put on five rings: one on her little finger, one on her middle finger and three on her ring finger. In how many different orders can she take them all off one by one?

(A) $16$ (B) $20$ (C) $24$ (D) $30$ (E) $45$

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