Suppose a simple random sample of size n=42 is obtained from a population with μ=65 and σ=16. (a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities regarding the sample mean? (b) Assuming the normal model can be used, determine P(x<68.1).

Suppose a simple random sample of size n=42 is obtained from a population with μ=65 and σ=16. (a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities regarding the sample mean? (b) Assuming the normal model can be used, determine P(x<68.1).

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

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Question

Suppose a simple random sample of size

n=42

is obtained from a population with

μ=65

and

σ=16.

(a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities regarding the sample mean?

(b) Assuming the normal model can be used, determine

P(x<68.1).

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