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UKMT Senior Kangaroo, 2025

Algebra Difficulty 3.0 AMC 10/12 Prove it United Kingdom

A teacher works out the number of different ways, $W$ , she can choose two students from Class A. She also works out the number of different ways, $V$ , she can choose two students from Class B. Class A has four more students in it than class B. She notices that $W = 3V$ . How many students are there in class A?

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