Suppose that a random variable has a standard normal distribution. Use a standard normal table such as this one to determine the probability that is between −1.33 and 0.67.

Give your answer in decimal form, precise to at least three decimal places.

(−1.33

Respuesta :

Using the normal distribution, it is found that there is a 0.6568 = 65.68% probability that the variable that is between −1.33 and 0.67.

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.

In this problem, we have a standard normal distribution, hence [tex]\mu = 0, \sigma = 1[/tex].

The probability that the variable is between −1.33 and 0.67 is the p-value of Z when X = 0.67 subtracted by the p-value of Z when X = -1.33, hence:

X = 0.67

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

[tex]Z = \frac{0.67 - 0}{1}[/tex]

[tex]Z = 0.67[/tex]

[tex]Z = 0.67[/tex] has a p-value of 0.7486.

X = -1.33

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

[tex]Z = \frac{-1.33 - 0}{1}[/tex]

[tex]Z = -1.33[/tex]

[tex]Z = -1.33[/tex] has a p-value of 0.0918.

0.7486 - 0.0918 = 0.6568.

0.6568 = 65.68% probability the variable that is between −1.33 and 0.67.

You can learn more about the normal distribution at https://brainly.com/question/24663213