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SEAMO 2027 - Paper F - SET 03 - Self-study Question 11

SEAMO · SEAMO 2027 - Paper F - SET 03 - Self-study

Question 11

How many distinct ways are there to arrange 4 girls and 10 boys to dance in a circle such that there are at least 2 boys between any two adjacent girls?

Counting convention: all dancers are distinct; rotations count as the same arrangement, while reflections count separately.
  1. $10!\cdot5!/2!$
  2. $10!\cdot4!/2!$
  3. $9!\cdot5!/2!$
  4. $9!\cdot4!/2!$
  5. None of the above