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Jack
10-10-2013, 11:19 AM
How many passwords can be created from 5 digits?
(A) 10^5
(B) 50
(C) 5!
(D) ^{10}C_{5}

miranda
10-10-2013, 11:21 AM
Every digit of the password can be chosen with 10 different ways. Therefore the number of possible passwords are 10*10*10*10*10=10^5.
The correct answer is (A)

Jack
10-10-2013, 11:21 AM
thanks!!:)