SOLUTION: Hello, having issues with this question, please help. Using the digits 0 – 9, find out how many 4 digit passcodes (Like 0056 or 3984) can be configured based on the stated cond

Algebra ->  Permutations -> SOLUTION: Hello, having issues with this question, please help. Using the digits 0 – 9, find out how many 4 digit passcodes (Like 0056 or 3984) can be configured based on the stated cond      Log On


   

Question 729775: Hello, having issues with this question, please help.
Using the digits 0 – 9, find out how many 4 digit passcodes (Like 0056 or 3984) can be configured based on the stated conditions.
The passcode can't start with a 0, a 1, or a 2 and no digits may be repeated.
Answer by fcabanski(1391) About Me  (Show Source):
You can put this solution on YOUR website!
There are 7 possibilities for the first digit.


Since digits cannot repeat, there are 10-1 possibilities for the second digit (you've already used one for the first digit).


There are 10-2 possibilities for the 3rd digit.


There are 10-3 possibilities for the 4th digit.


7*9*8*7 = 3528 possible pass codes.