Ajay
I just saw this video and at 10:55 why are we dividing by 3*2*1 rather than multiplying that factor.
Since, those bars have equal status each one of them should have the opportunity to be the first bar(so there are 3 ways of choosing the first bar), then after fixing the first bar, we go over the second bar(and we are left with 2 ways of choosing the second bar) and finally we put the last bar and there's only 1 way of choosing the 3rd bar. So, that comes out to be 3*2*1 ways.