Respuesta :
Using the binomial distribution, it is found that there is a 0.0368 = 3.68% probability that the teacher first draws Milani's name as the 7th student.
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, there are 20 students, hence in each question the probability that Milani's name is called is p = 1/20 = 0.05.
The probability that the teacher first draws Milani's name as the 7th student is P(X = 0) when n = 6(none during the first six) multiplied by 0.05(called during the seventh), hence:
P(X = 7) = (0.95)^6 x 0.05 = 0.0368.
0.0368 = 3.68% probability that the teacher first draws Milani's name as the 7th student.
More can be learned about the binomial distribution at https://brainly.com/question/24863377
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