Q21 of 43 Page 296

Seven persons are to be seated in a row. The probability that two particular persons sit next to each other is

Given that 7 persons are to be seated in a row.

If two persons sit next to each other, then consider these two persons as 1 group.


Now we have to arrange 6 persons.


∴ Number of arrangement = 2! × 6!


Total number of arrangement of 7 persons = 7!






Hence, the correct option is (C).

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