Using the normal distribution, the probabilities are given as follows:
a. 0.4602 = 46.02%.
b. 0.281 = 28.1%.
<h3>Normal Probability Distribution</h3>The z-score of a measure X of a normally distributed variable with mean and standard deviation
is given by:
- The z-score measures how many standard deviations the measure is above or below the mean.
- Looking at the z-score table, the p-value associated with this z-score is found, which is the percentile of X.
- By the Central Limit Theorem, the sampling distribution of sample means of size n has standard deviation
.
The parameters are given as follows:
Item a:
The probability is <u>one subtracted by the p-value of Z when X = 984</u>, hence:
Z = 0.1
Z = 0.1 has a p-value of 0.5398.
1 - 0.5398 = 0.4602.
Item b:
By the Central Limit Theorem:
Z = 0.58
Z = 0.58 has a p-value of 0.7190.
1 - 0.719 = 0.281.
More can be learned about the normal distribution at brainly.com/question/4079902
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