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प्रश्न
In how many ways can six persons be seated in a row?
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उत्तर
Number of seats available to the first person = 6
Number of seats available to the second person = 5
Number of seats available to the third person = 4
Number of seats available to the fourth person = 3
Number of seats available to the fifth person = 2
Number of seats available to the sixth person = 1
Total number of ways of making the seating arrangement = `6xx5xx4xx3xx2xx1=720`
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