SOLUTION: How many 7 digit phone numbers are possible if order matters?

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Question 619626: How many 7 digit phone numbers are possible if order matters?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How many 7 digit phone numbers are possible if order matters?
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With Repetition: 10^7
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Without Repetition: 10P7 = 10!/(10-7)! = 10*9*8*7*6*5*4
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Cheers,
Stan H.