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UKMT Pink Kangaroo, 2024

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Lil writes one of the letters P, Q, R, S in each cell of a $2 \times 4$ table. She does this in such a way that, in each row and in each $2 \times 2$ square, all four letters appear. In how many ways can she do this?

(A) $12$ (B) $24$ (C) $48$ (D) $96$ (E) $198$

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