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UKMT Intermediate Mathematical Challenge, 2019

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

Megan writes down a list of five numbers. The mean of her first three numbers is $-3$ . The mean of her first four numbers is $4$ . The mean of her first five numbers is $-5$ . What is the difference between her fourth number and her fifth number?

(A) $66$ (B) $55$ (C) $44$ (D) $33$ (E) $22$

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