Thread: Combination Lock

Hello,

I have been wracking my brain trying to figure out this problem, any help would be greatly appreciated.

A typical "combination" lock is opened with the correct sequence of three numbers between 0 and 49 inclusive (A number can be used more than once.) What is the probability of guessing those three numbers and opening the lock with the first try?

What I have been doing is a permutation (since order does matter) but I'm unsure if I have the right answer.

P
50 3

= 1/117600 chance

Please offer any advice or answers, I would be most grateful.

Note that numbers can be repeated.
Hence the probability is: