Let:
A = Draw a king
B = Draw a queen
C = Draw a Jack
a = Number of kings
b = Number of queens
c = Number of jacks
N = Total number of cards
Since the events are mutually exclusive:
[tex]\begin{gathered} P(A\cup B\cup C)=\frac{a}{N}+\frac{b}{N}+\frac{c}{N} \\ where \\ a=4 \\ b=4 \\ c=4 \\ N=52 \\ so\colon \\ P(A\cup B\cup C)=\frac{4}{52}+\frac{4}{52}+\frac{4}{52}=\frac{12}{52}=\frac{3}{13} \end{gathered}[/tex]Answer:
A. 3/13
