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UKMT Junior Kangaroo, 2016

Number theory Difficulty 1.0 Junior Find the answer United Kingdom

Joey calculated the sum of the largest and smallest two-digit numbers that are multiples of three. Zoë calculated the sum of the largest and smallest two-digit numbers that are not multiples of three. What is the difference between their answers?

(A) $2$ (B) $3$ (C) $4$ (D) $5$ (E) $6$

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