SOLUTION: Three people enter a main floor elevator of the Mathematical Sciences Building. Assuming each individual will get off the elevator at any one of floors 2 through 7 (six floors) and

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Question 798490: Three people enter a main floor elevator of the Mathematical Sciences Building. Assuming each individual will get off the elevator at any one of floors 2 through 7 (six floors) and do so independently of each other, what is the chance that 3 all will get off on the same floor. Give 3 digits after the decimal
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Let the three people be Tom, Dick, and Harry.

The probability that Tom will get off on one of the floors is 1, since
it is certain that he will.

The probability that Dick will get off on the same floor that Tom
got off on is 1/6.

The probability that Harry will then get off on the same floor that Tom
and Dick got off on is 1/6.

Answer: 1×1%2F6×1%2F6 = 1%2F36 = 0.027777... round to 0.278

Edwin