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प्रश्न
Write the number of ways in which 5 boys and 3 girls can be seated in a row so that each girl is between 2 boys ?
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उत्तर
B_B_B_B_B
Five boys can be arranged amongst themselves in 5! ways, at the places shown above.
The three girls are now to be arranged in the remaining four places taken three at a time = 4P3 = 4!
By fundamental principle of counting, total number of ways = 5! x 4! = 120 x 24= 2880
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