Answer:
The number of ways of selection of 3 items taking 2 at a time in addition to the possible ways in which each girl selects the same style is 9 different ways. Since the list contains 9 different ways in which each of them can select a style, the list is complete.
Explanation:
Here we have the number of ways the available styles can be arranged between each girl is given by the number of permutation of 3 items, taking two at a time plus the number of possible selections where both of them select the same style as follows
We note that the formula for permutation is
P
=
Therefore āPā =
= 6 different ways
The number of possible selections where both of them select the same style is given by
(T, T), (s, s), (L, L) = 3 different ways
Total number of ways = 6 + 3 = 9 ways
Number of different ways available in the list = 9 ways
Therefore the list is complete