Answer:
3600 ways
Explanation:
person A has 7 places to choose from :
→ He has 2 places ,one to the extreme left of the line ,the other to the extreme right of the line
If he chose one of those two ,person B will have 5 choices and the other 5 persons will have 5! Choices.
⇒ number of arrangements = 2×5×5! = 1 200
→ But Person A also , can choose one of the 5 places in between the two extremes .
If he chose one of those 5 ,person B will have 4 choices and the other 5 persons wil have 5! Choices.
⇒ number of arrangements = 5×4×5! = 2 400
In Total they can be arranged in :
1200 + 2400 = 3600 ways