Permutations & Combinations
Permutation and Combination
star_batch_jee_advanced_2025
Grade 11
Step-by-Step Solution
Key Concept: Permutations adjust based on symmetry constraints—linear arrangements use $n!$, circular use $(n-1)!$, and identical arrangements divide by the number of identical configurations.
The number of ways to seat 12 persons depends on the seating arrangement context. For linear arrangement: $12!$ ways. For circular arrangement: $ rac{12!}{12} = 11!$ ways (fixing one person to account for rotational symmetry). For arrangement in two rows of 6: $ rac{12!}{2}$ ways (if rows are identical). For circular table with specific constraints, we use $11!$ since rotations are equivalent but reflections are distinct.
Correct Answer: [A-s] [B-r] [C-p] [D-q]