Respuesta :
Answer:
The probability that the sample will contain exactly three successes is 0.2668.
Step-by-step explanation:
Given information:
Sample size = 10
Probability of a success, p=0.30
Probability of a failure q=1-p = 1-0.30 = 0.70
The binomial formula to determine the probability is
[tex]P(X=r)=^nC_rp^rq^{n-r}[/tex]
where, n is the sample size, r is required number of success, p is probability of success and q is probability of failure.
We need to find the probability that the sample will contain exactly three successes.
[tex]P(X=3)=^{10}C_3(0.30)^3(0.70)^{10-3}[/tex]
[tex]P(X=3)=^{10}C_3(0.30)^3(0.70)^{7}[/tex]
[tex]P(X=3)=(120)(0.0022235661)[/tex]
[tex]P(X=3)=0.266827932[/tex]
[tex]P(X=3)\approx 0.2668[/tex]
Therefore the probability that the sample will contain exactly three successes is 0.2668.
Using the binomial distribution, it is found that there is a 0.2668 = 26.68% probability that the sample will contain exactly three successes.
What is the binomial distribution formula?
The formula is:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters are:
- x is the number of successes.
- n is the number of trials.
- p is the probability of a success on a single trial.
In this problem:
- The sample size is of n = 10.
- The probability of a success is of p = 0.3.
The probability that the sample will contain exactly three successes is P(X = 3), hence:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = x) = C_{10,3}.(0.3)^{3}.(0.7)^{7} = 0.2668[/tex]
More can be learned about the binomial distribution at https://brainly.com/question/24863377