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IKMC 2017 - Grades 9-10 - Self-study Question 24

IKMC · IKMC 2017 - Grades 9-10 - Self-study

Question 24

A seven-digit password contains each used digit exactly as many times as that digit’s value, with all equal digits consecutive. Examples: 4444333 or 1666666. How many passwords are possible?
  1. 6
  2. 7
  3. 10
  4. 12
  5. 13