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IMAS 2021 — Upper Primary Grades 5–6 — Round 1 Question 15

IMAS · IMAS 2021 — Upper Primary Grades 5–6 — Round 1

Question 15

How many ways can we arrange two 1’s, two 2’s and two 3’s in a row such that there is at least one “2” between two 1’s, at least one “3” between two 2’s and at least one “1” between two 3’s?
  1. 10
  2. 11
  3. 12
  4. 13
  5. 14