Question 875238
10P4 = 5040 = {{{10!/6! = 10*9*8*7}}}
Re TY: one would have to generate the 5040 ways themselves.
The best way of understanding it is:
10 choices for 1st & 9 different choices for 2nd &  8 different choices for 3rd
& finally 7 different choices for the 4th number: {{{10*9*8*7}}} ways to do all this