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UKMT Pink Kangaroo, 2024

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

A number is written in each of the twelve circles shown. The number inside each square indicates the product of the numbers at its four vertices. What is the product of the numbers in the eight grey circles?

(A) $20$ (B) $40$ (C) $80$ (D) $120$ (E) $480$

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