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1 The null hypothesis Both a and b are correct. 2 The alternate hypothesis Is accepted if the null hypothesis is rejected. 3 The level of significance All of the above. 4 A Type I error is Rejecting the null hypothesis when it is true 5 The critical value is The point that divides the acceptance region from the rejection region. 6 In a one-tailed test The rejection region is in one of the tails. 7 To conduct a one sample test of means and use the z distribution as the test statistic We can use the sample standard deviation provided n is at least 30. 8 A p-value is The probability of finding a value of the test statistic this extreme when the null hypothesis is true. 9 A Type II error occurs when We accept a false null hypothesis. 10 Which of the following statements are correct when deciding whether to use the z or the t distribution? All of the above statements are correct. 11 In a two-sample test of means for independent samples, the equal sign always appears in The null hypothesis. 12 In a two-sample test of means for independent samples, we use the z distribution when Both samples are at least 30. 13 Which of the following is a requirement for a two-sample test for independent samples. Both samples are independent. 14 A random sample of 10 observations is selected from the first normal population and 8 from the second normal population. For a one-tailed test of hypothesis (.01 significance level) to determine if there is a difference in the population means, the degrees of freedom are 16 15 Which of the following is not necessary to determine a p-value? The level of significance. Q1. A recent article in a computer magazine suggested that the mean time to fully learn a new software program is 40 hours. A sample of 100 first-time users of a new statistics program revealed the mean time to learn it was 39 hours with the standard deviation of 8 hours. At the 0.05 significance level, can we conclude that users learn the package in less than a mean of 40 hours? a. State the null and alternate hypotheses. H0:u=40 ___________________________________________________________________ _ H1:u<40 ___________________________________________________________________ _ b. State the decision rule. If the p-value is less than or equal to 0.05, the null hypothesis is rejected and there is evidence to conclude the population mean to learn the package is less than 40 hours. ___________________________________________________________________ ___ c. Compute the value of the test statistic. d. Compute the p-value. c. t = (39 - 40)/(8÷√100)=1.25, df=n-1=99 d. p =.107123 e. What is your decision regarding the null hypothesis? Interpret the result. Since the p-value is greater than .05, we fail to reject the null hypothesis and conclude that there is no evidence to conclude that the true mean time to learn the package is less than 40 hours. ___________________________________________________________________ ___________________________________________________________________