The Marina Slip Puzzle
Posted: Thu Dec 24, 2015 3:20 pm
This may be something fun to work on over the holidays, a little puzzle.
Suppose you are on a North-Channel-of-Lake-Huron cruise in a big fleet of Boston Whaler boats, 25-boats in total. The fleet comes to a marina which has exactly 25-slips, all unoccupied and waiting for the fleet to arrive. The fleet has made reservations, and every boat in the fleet has been pre-assigned a slip. There is a little problem, because the first boat in the fleet to enter the marina has lost the email with his slip reservation. He figures, what the heck, "I'll just take a slip at random," and he does.
You are the last boat in the fleet to arrive at the marina, and all 24 other boats are already in slips. What are the odds that your assigned slip will be vacant when you enter the marina?
Suppose you are on a North-Channel-of-Lake-Huron cruise in a big fleet of Boston Whaler boats, 25-boats in total. The fleet comes to a marina which has exactly 25-slips, all unoccupied and waiting for the fleet to arrive. The fleet has made reservations, and every boat in the fleet has been pre-assigned a slip. There is a little problem, because the first boat in the fleet to enter the marina has lost the email with his slip reservation. He figures, what the heck, "I'll just take a slip at random," and he does.
You are the last boat in the fleet to arrive at the marina, and all 24 other boats are already in slips. What are the odds that your assigned slip will be vacant when you enter the marina?