# Hypothesis test for a population mean

Not what you're looking for?

Please help with the following problem.

You have a sample size of 120 and the population standard deviation of 20. You are testing the null hypothesis of whether the population mean is 120 or not.

A. What are the critical values for rejection when Type I error is 5%?

B. If actual mean is 121, find the Type II error

C. Draw the Type I and II errors

##### Purchase this Solution

##### Solution Summary

This is an example of a Hypothesis test for a population mean. The solution also illustrates Type I and Type II errors.

##### Solution Preview

Please see he attached Word document.

Hypothesis test, critical values for rejection

You have a sample size of 120 and the population standard deviation of 20. You are testing the null hypothesis of whether the population mean is 120 or not.

A. What are the critical values for rejection when Type I error is 5%?

This is a large sample hypothesis test regarding a population mean. The test statistic such a hypothesis test has a standard normal, or Z distribution (a normal distribution with mean equal to 0 and standard deviation equal to 1). The ...

##### Purchase this Solution

##### Free BrainMass Quizzes

##### Measures of Central Tendency

This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.

##### Measures of Central Tendency

Tests knowledge of the three main measures of central tendency, including some simple calculation questions.

##### Terms and Definitions for Statistics

This quiz covers basic terms and definitions of statistics.

##### Know Your Statistical Concepts

Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.