/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 7 a. Find a \(z_{0}\) such that \(... [FREE SOLUTION] | 91Ó°ÊÓ

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a. Find a \(z_{0}\) such that \(P\left(z>z_{0}\right)=.025 .\) b. Find a \(z_{0}\) such that \(P\left(z

Short Answer

Expert verified
b) The probability of \(z\) being less than \(z_{0}\) is equal to 0.9251? a) \(z_{0} \approx 1.96\) b) \(z_{0} \approx 1.44\)

Step by step solution

01

Recall the standard normal distribution table

To solve this exercise, we will use the standard normal distribution table, also known as the Z-table, which provides us the probabilities associated with specific z-scores in a standard normal distribution. If you have access to a calculator with the inverse cumulative distribution function, you can use this as well.
02

Find \(z_{0}\) for part a

For part a, we want to find \(z_{0}\) such that \(P(z>z_{0}) = 0.025\). Since the normal distribution is symmetric, we can re-write this as \(P(z<-z_{0}) = 0.025\). Now, using the standard normal distribution table or a calculator, we look for the value of \(z_{0}\) where the probability of \(z\) being less than \(-z_{0}\) is 0.025. We find that this value is approximately \(z_{0} = 1.96\).
03

Find \(z_{0}\) for part b

For part b, we want to find \(z_{0}\) such that \(P(z<z_{0}) = 0.9251\). Using the standard normal distribution table or a calculator, we look for the value of \(z_{0}\) where the probability of \(z\) being less than \(z_{0}\) is 0.9251. We find that this value is approximately \(z_{0} = 1.44\).
04

Final Answers

a. \(z_{0} \approx 1.96\) b. \(z_{0} \approx 1.44\)

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