Given:
The total number of digits =10.
We need to create 2 digits passcode.
We can not repeat the digits.
II would appreciate your feedback - you can provide it by rating the session.n this case, we can use
[tex]nP_r=\frac{n!}{(n-r)!}[/tex]Substitute n=10 and r=2, we get
[tex]10P_2=\frac{10!}{(10-2)!}[/tex][tex]10P_2=\frac{10\times9\times8!}{8!}[/tex][tex]10P_2=90[/tex]We can create 90 different 2 digits passcode.