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IMAS 2019 — Upper Primary Grades 5–6 — Round 2 Question 14

IMAS · IMAS 2019 — Upper Primary Grades 5–6 — Round 2

Question 14

The four digits 2, 0, 1 and 9 are used to form all 18 possible four-digit numbers, then add a positive integer n to each of these numbers, so that the remainder of each sum when divided by 11 is not 1. Now, all positive integers n satisfying the above conditions are listed from small to large. What is the sum of the first five numbers?