TITLE: How many $4$ digit numbers with distinct digits can be formed using $0,1,2,3,4,5$?
QUESTION [5 upvotes]: So left most digit can be filled with $5$ (can't use $0$ there) then next one got $5$ option then $4$ and $3$. So the answer is $5\cdot 5\cdot 4\cdot 3 =300$. Is it correct ?

REPLY [2 votes]: Community wiki answer so that the question can be marked answered:
As stated in the comments, your calculation is correct.