SOLUTION: Evaluate each factorial expression. 20!/2!18!

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Question 481833: Evaluate each factorial expression.
20!/2!18!
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
20!/18! = 20*19*18!/18! = 20*19 See that? All other terms cancel.
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20!/2!18! = 20*19/2 = 190