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UKMT Senior Mathematical Challenge, 2024

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

In the following expressions, $x$ is non-zero. When one of these expressions is removed, the mean of the remaining four is $11x$ . Which expression is removed?

(A) $4x$ (B) $8x$ (C) $12x$ (D) $16x$ (E) $20x$

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