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IKMC 2027 - Grades 9-10 - Self-study SET 6 - Thematic Batch 3 Question 22

IKMC · IKMC 2027 - Grades 9-10 - Self-study SET 6 - Thematic Batch 3

Question 22

At an unusual party, each boy must wear one yellow sock and one blue sock, and each girl one pink sock and one yellow sock. A group of n friends buys socks as cheaply as possible. All socks are the same size and are sold only in same-colour pairs. How many pairs must they buy?

Question illustration
  1. Either n or n+1 pairs, depending on the group.
  2. If all friends are of the same gender, they certainly buy only n pairs.
  3. Either n+1 or n+2 pairs, depending on the group.
  4. They need n+1 pairs if and only if n is odd.
  5. They need n+1 pairs if and only if n is even.