The explanation for similar problems say that to use the permutation equation,
the order does not need to matter. However, for the combination equations, the
order does matter.
No, that's exact;ly backwards! Order matters with PERMUTATIZONS,
Order does not matter with COMBINATIONS.
(a) From the 13 albums released by a musician, the recording company wishes to
release 9 in a boxed set. How many different boxed sets are possible?
This depends on whether or not you would consider it to be a different boxed set
if the CD on the top of the stack in the box were swapped with the second one,
or whether it would still be considered the same boxed set if you switched
the order in which they were packaged in the box.
Considering it to be a different boxed set to change the order,
the answer would be
13P9 = 259459200
Considering it to be the same boxed set even if you changed the order in
which they were packed in the box, the answer would be
13C9 = 715
(b) How many different committees of size 3 can be formed from 13 people?
Since the committee consisting of Tom, Dick and Harry is the same
committee consisting of Harry, Tom, and Dick, we use combinations:
13C3 = 286
E$dwin
