Answer:
[tex]Pr = \frac{1}{6}[/tex]
Step-by-step explanation:
Given
[tex]Cards = \{A,B,C,D,E,F\}[/tex]
[tex]r = 2[/tex] --- selection
Required
Probability of choosing a pair with only B, C and F
The total selection is: 36
This is calculated as thus:
[tex]First = 6[/tex] --- First selection can be any of the 6 cards
[tex]Second = 6[/tex] --- Second selection can be any of the 6 cards [No restriction]
So, we have:
[tex]n = First * Second[/tex]
[tex]n = 6 * 6[/tex]
[tex]n = 36[/tex]
The pair of only B, C or F is:
[tex]Pair = \{(B,C), (B,F), (C,B),(C,F),(F,B),(F,C)\}[/tex]
[tex]n(Pair) = 6[/tex]
So, the probability is:
[tex]Pr = \frac{n(Pair)}{n}[/tex]
[tex]Pr = \frac{6}{36}[/tex]
Simplify
[tex]Pr = \frac{1}{6}[/tex]