[tex]P(A)=\dfrac{|A|}{|\Omega|}\\\\
|\Omega|={6+2-1\choose 2}={7\choose 2}=\dfrac{7!}{2!5!}=\dfrac{6\cdot7}{2}=21\\\\
a)\\
A=\{(1,6),(2,6),(3,6),(4,6),(5,6),(6,6),(2,5),(3,5),(4,5),(5,5),\\
(3,4),(4,4)\}\\
|A|=12\\
P(A)=\dfrac{12}{21}=\dfrac{4}{7}\\\\
b)\\
A=\{(1,1),(1,2),(1,3),(1,4),(1,5),(1,6),(2,2),(2,3),(2,4),(2,5),\\
(3,3),(3,4)\}\\
|A|=12\\
P(A)=\dfrac{12}{21}=\dfrac{4}{7}[/tex]
