SOLUTION: A computer system requires users to have an access code that consists of a three-digit number that is not allowed to start with zero and cannot repeat digits. How many such codes a

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Question 448434: A computer system requires users to have an access code that consists of a three-digit number that is not allowed to start with zero and cannot repeat digits. How many such codes are possible?
Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!

for first position: 9 ways (except 0)
for second position : 9 ways (except that position first)
for third position : 8 ways (except that position first and second)

number of possible codes = 9*9*8 = 648