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UKMT Grey Kangaroo, 2024

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

Farmer Fi is selling chicken and duck eggs. She has baskets holding 4, 6, 12, 13, 22 and 29 eggs. Her first customer buys all the eggs in one basket. Fi notices that the number of chicken eggs she has left is twice the number of duck eggs. How many eggs did the customer buy?

(A) $4$ (B) $12$ (C) $13$ (D) $22$ (E) $29$

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