A four-person committee is chosen from a group of eight boys and six girls. If students are chosen at random, what is the probability that the committee consists of all boys?

A. [tex]\frac{4}{1001}[/tex]
B. [tex]\frac{15}{1001}[/tex]
C. [tex]\frac{10}{143}[/tex]
D. [tex]\frac{133}{143}[/tex]



Answer :

To determine the probability that a randomly chosen four-person committee consists of all boys from a group of eight boys and six girls, we follow these steps:

1. Calculate the total number of ways to form a four-person committee from the 14 students (8 boys and 6 girls):

The total number of ways to choose 4 people out of 14 can be found using the combination formula:
[tex]\[ \binom{14}{4} \][/tex]

2. Determine the number of ways to form an all-boys committee:

Since there are 8 boys, we need to calculate the number of ways to choose 4 boys out of 8:
[tex]\[ \binom{8}{4} \][/tex]

3. Calculate the probability:

The probability that the committee consists of all boys is the ratio of the number of all-boys committees to the total number of committees:
[tex]\[ \text{Probability} = \frac{\binom{8}{4}}{\binom{14}{4}} \][/tex]

Given the calculations:

- The total number of four-person committees from 14 students is:
[tex]\[ \binom{14}{4} = 1001 \][/tex]

- The number of four-person committees consisting entirely of boys is:
[tex]\[ \binom{8}{4} = 70 \][/tex]

Therefore, the probability that a four-person committee consists of all boys is:
[tex]\[ \text{Probability} = \frac{70}{1001} \][/tex]

Now, let's match this fraction to one of the given options:

[tex]\[ \frac{4}{1001}, \quad \frac{15}{1001}, \quad \frac{10}{143}, \quad \frac{133}{143} \][/tex]

The fraction [tex]\(\frac{70}{1001}\)[/tex] is equivalent to approximately 0.06993, which matches the given answer exactly.

Thus, the correct option is:
[tex]\[ \boxed{\frac{10}{143}} \][/tex]