# 7 persons to be seated in a row. Probability that 2 particular persons to sit next to each other is

1) 3/7

2) 2/7

3) 4/7

4) 5/7

Solution: Option (2) 2/7

Total cases = 7!

Favourable cases = 2. 6!

Hence, the required probability = (2.6!)/7! = 2/7.