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Compute z-scores given populations and sample size

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For a population with a mean of 60 and a standard deviation of 24, find the z-score corresponding to each of the following samples.

a. M = 63 for a sample of n = 16 scores
b. M = 63 for a sample of n = 36 scores
c. M = 63 for a sample of n = 64 scores

A population of scores forms a normal distribution with a mean of 40 and a standard deviation of 12.

a. What is the probability of randomly selecting a score less than X = 34?
b. What is the probability of selecting a sample of n = 9 scores with a mean less than M = 34?
c. What is the probability of selecting a sample of n = 36 scores with a mean less than M = 34?

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Solution Summary

Provides steps necessary to determine z-score corresponding to each sample.

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(1) z = (M - mu)/(sigma/sqrt n)

(a) z = (63 - 60)/(24/sqrt 16) = 0.5

(b) z = (63 - 60)/(24/sqrt 36) = ...

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