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Find the number of ways in which 4 boys and 5 girls can be arranged in a row so that no two boys are together and no two girls are together. |
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Answer» No two boys and no two girls are together means the boys & girls must sit alternately. Four boys can be permuted in 4! ways & the 5 girls in 5! ways. ∴ The total number of ways is 5! × 4! ways. |
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