Study Unit 2, Chapter 2, Topic 1: Copyright ©2012 SIM UNIVERSITY. All rights reserved.1Hypothesis Tests:One Sample – Two-Tail Test

OutlineCopyright ©2012 SIM UNIVERSITY. All rights reserved.2Conduct a test of hypothesis about a population mean using the five-step hypothesis-testing procedure.

Testing for a Population Mean with aKnown Population Standard Deviation- ExampleThe Internal Revenue Service (IRS) is interested in estimating the mean amount of money spent on outside tax service by income tax filers filing as single on their individual form. The mean amount of money spent on outside tax service follows a normal distribution with a mean of $90 and the population standard deviation is assumed to be $30.79.The director at IRS has implemented a series of initiatives to reduce the paper work required, hoping that this could translate to lower cost incurred during filing of income tax. To analyze the impact, they have selected a random sample of n = 200 people