After Eduardo's 11th game that ended in extra innings, Alicia told him that his team is weird because they play so many games with extra innings. Eduardo argues that it is just part of baseball and since they have played so many games (95 total since the team was formed) it is normal to have some games go long. To settle the argument, Eduardo decides to use the CLT. He finds that the percentage of games that go into extra innings is 7.6% and decides to find the probability that, in a simple random sample of 95 games, 11 or more of them end in extra innings.

Respuesta :

Using the normal approximation to the binomial distribution, by the Central Limit Theorem, it is found that there is a 0.102 = 10.2% probability that, in a simple random sample of 95 games, 11 or more of them end in extra innings.

Normal Probability Distribution

In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

  • It measures how many standard deviations the measure is from the mean.
  • After finding the z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X.
  • The binomial distribution is the probability of x successes on n trials, with p probability of a success on each trial. By the Central Limit Theorem, it can be approximated to the normal distribution with [tex]\mu = np, \sigma = \sqrt{np(1-p)}[/tex].

In this problem:

  • The percentage of games that go into extra innings is 7.6%, hence p  = 0.076.
  • His teams played 95 games, hence n = 95.

The mean and the standard deviation are given by:

[tex]\mu = np = 95(0.076) = 7.22[/tex]

[tex]\sigma = \sqrt{np(1-p)} = \sqrt{95(0.076)(0.924)} = 2.5829[/tex]

Using continuity correction, as the normal distribution is continuous and the binomial is discrete, the probability that, in a simple random sample of 95 games, 11 or more of them end in extra innings is P(X > 11 - 0.5) = P(X > 10.5), which is 1 subtracted by the p-value of Z when X = 10.5.

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{10.5 - 7.22}{2.5829}[/tex]

[tex]Z = 1.27[/tex]

[tex]Z = 1.27[/tex] has a p-value of 0.898.

1 - 0.898 = 0.102

0.102 = 10.2% probability that, in a simple random sample of 95 games, 11 or more of them end in extra innings.

More can be learned about the normal approximation to the binomial distribution at https://brainly.com/question/14424710