SOLUTION: How many ways can 12 people be seated in 20 chairs?

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Question 234156: How many ways can 12 people be seated in 20 chairs?
Answer by nyc_function(2741) About Me  (Show Source):
You can put this solution on YOUR website!
Use the permutation formula:
nPr = n!/(n - r)!
n = 20 and r = 12
Plug and chug.
20P12 = 20!/(20 - 12)!
20P12 = (20x19x18x17x16x15x14x13x12x11x10x9x8)/40,320
Can you finish now?
Just use your calculator to divide top by the bottom.