Explanation:
FCP fundamental counting principle :
in total there are
3×3×2 = 18
different combinations
listing method means listing all different triplets of such outfit combinations.
white shirt = ws
red blouse = rb
floral shirt = fs
short = sh
jeans = j
jogger pants = jp
shoes = s
sandals = sa
{
(ws, sh, s),
(ws, sh, sa),
(ws, j, s),
(ws, j, sa),
(ws, jp, s),
(ws, jp, sa),
(rb, sh, s),
(rb, sh, sa),
(rb, j, s),
(rb, j, sa),
(rb, jp, s),
(rb, jp, sa),
(fs, sh, s),
(fs, sh, sa),
(fs, j, s),
(fs, j, sa),
(fs, jp, s),
(fs, jp, sa)
}
tree diagram (I cannot draw here) :
OOTD
/ | \
ws rb fs
/ | \ / | \ / | \
sh j jp sh j jp sh j jp
/ | / | / | / | / \ / | / | / | / |
s sa s sa s sa s sa s sa s sa s sa s sa s sa
as you can see, we get a expected 18 different triplets in our listed set, and we get 18 different end leaves in and therefore 3-level paths through our tree.