Last Puzzles (Tricky Probabilty Problem To Solve)

Aishwarya was first to board to her flight to delhi. She forgot her seat number and picks a random seat for herself. After this, every single person who get to the flight sits on his seat if its available else chooses any available seat at random. Abhishek is last to enter the flight and at that moment 99/100 seats were occupied. Whats the probability what Abhishek gets to sit in his own seat ?

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