Join IDNLearn.com and start getting the answers you've been searching for. Our experts are ready to provide in-depth answers and practical solutions to any questions you may have.

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}{\sqrt{10001}}[/tex]
C. [tex]\frac{10}{143}[/tex]
D. [tex]\frac{133}{143}[/tex]


Sagot :

To find the probability that a randomly selected four-person committee consists of all boys from a group of 8 boys and 6 girls, we can follow these steps:

1. Determine the Total Number of Boys and Girls:
- There are 8 boys.
- There are 6 girls.
- Total students = 8 boys + 6 girls = 14 students.

2. Calculate the Total Number of Ways to Form a Four-Person Committee from 14 Students:
- The number of ways to choose 4 students out of 14 (regardless of gender) is given by the combination formula [tex]\(\binom{n}{k}\)[/tex], which is [tex]\(\frac{n!}{k!(n-k)!}\)[/tex], where [tex]\(n\)[/tex] is the total number of students and [tex]\(k\)[/tex] is the number of students to choose.
- Thus, the total number of ways to form a committee of 4 from 14 students is [tex]\(\binom{14}{4} = \frac{14!}{4!(14-4)!} = \frac{14!}{4! \cdot 10!} = 1001\)[/tex].

3. Calculate the Number of Ways to Form a Four-Person Committee Comprised Entirely of Boys:
- The number of ways to choose 4 boys out of 8 (since we want the committee to consist only of boys) is also given by the combination formula.
- Thus, the number of ways to choose 4 boys out of 8 is [tex]\(\binom{8}{4} = \frac{8!}{4!(8-4)!} = \frac{8!}{4! \cdot 4!} = 70\)[/tex].

4. Calculate the Probability:
- The probability of forming a four-person committee that consists entirely of boys is the ratio of the number of favorable outcomes (all boys) to the total number of possible outcomes (any gender).
- So, the probability is [tex]\(\frac{\text{Number of ways to choose 4 boys out of 8}}{\text{Total number of ways to choose 4 students out of 14}}\)[/tex] which simplifies to [tex]\[ \frac{70}{1001} \approx 0.06993006993006994. \][/tex]

5. Match the Probability with the Given Options:
- Comparing [tex]\(\frac{70}{1001}\)[/tex] to the given options:
- [tex]\(\frac{4}{1001}\)[/tex]
- [tex]\(\frac{15}{\sqrt{10001}}\)[/tex]
- [tex]\(\frac{10}{143}\)[/tex]
- [tex]\(\frac{133}{143}\)[/tex]

- Clearly, [tex]\(\frac{70}{1001}\)[/tex] matches [tex]\(\frac{10}{143}\)[/tex].

Therefore, the correct answer is [tex]\(\boxed{\frac{10}{143}}\)[/tex].
Thank you for using this platform to share and learn. Keep asking and answering. We appreciate every contribution you make. Your search for answers ends at IDNLearn.com. Thanks for visiting, and we look forward to helping you again soon.