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UKMT Grey Kangaroo, 2018

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Martha multiplied two 2-digit numbers correctly on a piece of paper. Then she scribbled out three digits as shown. What is the sum of the three digits she scribbled out?

(A) $5$ (B) $6$ (C) $9$ (D) $12$ (E) $14$

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