SOLUTION: To how many patrons could a telephone company furnish numbers having five digits, the first digit not being zero?

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Question 1133851: To how many patrons could a telephone company furnish numbers having five digits, the first digit not being zero?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

There are 5 ways to pick the first digit [1-5]
Next, there are 5 ways to pick the second digit [0 plus the remaining 4 from the first digit]
The 3rd digit is chosen from the remaining 4 numbers.
The 4th digit is chosen from the remaining 3 numbers.
The 5th digit is chosen from the remaining 2 numbers.

So, in summary, there are 5%2A5%2A4%2A3%2A2=600 ways.