Respuesta :
Answer: The correct option is (B) [tex]\dfrac{14}{33}.[/tex]
Step-by-step explanation: Given that a family has 8 girls and 4 boys. A total of 2 children must be chosen to speak on the behalf of the family at a local benefit.
We are to find the probability that 2 girls and no boys are chosen.
Total number of children in the family = 8 + 4 =12.
Let S denote the sample space of choosing 2 children from the family of 12 children and A denote the event of choosing 2 girls and no boys.
Then, according to the given information, we have
[tex]n(S)=^{12}C_2=\dfrac{12!}{2!(12-2)!}=\dfrac{12\times11\times10!}{2\times1\times10!}=66,\\\\\\n(A)=^8C_2\times^4C_0=\dfrac{8!}{2!(8-2)!}\times1=\dfrac{8\times7\times6!}{2\times1\times6!}=28.[/tex]
Therefore, the probability of event A is given by
[tex]P(A)=\dfrac{n(A)}{n(S)}=\dfrac{28}{66}=\dfrac{14}{33}.[/tex]
Thus, the required probability is [tex]\dfrac{14}{33}.[/tex]
Option (B) is CORRECT.