a stock broker has kept a daily record of the value of a particular stock over the years and finds that the prices of the stock form a normal distribution with a mean of $8.52 with a standard deviation of $2.38 the stock price beyond which 0.05 of the distribution fall is

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Answer:

The stock price beyond which 0.05 of the distribution fall is $12.44.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

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

The Z-score 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. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Mean of $8.52 with a standard deviation of $2.38

This means that [tex]\mu = 8.52, \sigma = 2.38[/tex]

The stock price beyond which 0.05 of the distribution fall is

This is the 100 - 5 = 95th percentile, which is X when Z has a pvalue of 0.95. So X when Z = 1.645.

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

[tex]1.645 = \frac{X - 8.52}{2.38}[/tex]

[tex]X - 8.52 = 1.645*2.38[/tex]

[tex]X = 12.44[/tex]

The stock price beyond which 0.05 of the distribution fall is $12.44.