Minnie has homework from 6 subjects including calculus and statistics this week.
Among them, she wants to finish homework for 4 subjects including calculus and
statistics today. She wants to finish statistics before calculus. How many ways are
there for her to select the 4 subjects, and then decide the order of doing homework?

My Work: $\binom 42 = 6$ (Ways to select 2 subjects that are not Calc and Stat to make 4 subjects in total).

Then $P(4,4) = 24$ (Ways to order those four subjects). But then you divide by $4$ to get $6$ ways to order them to get stat before calc like the question asks.

So $6 \times 6 = 36$ ways in total. But other answers I see give $72$? What am I doing wrong?

Any Help/Tips would be appreciated.
Thank You.