The personnel manager of a large retail clothing store suspects a difference in the mean amount of break time taken by workers during the weekday shifts compared with that of the weekend shifts. It is suspected that the weekday workers take longer breaks on average. A random sample of 46 weekday workers had a mean x1 = 53 minutes of break time. A random sample of 40 weekend workers had a mean x2 = 47 minutes. Previous studies show that the population standard deviation is 7 minutes and 9 minutes. Test the manager's suspicion at the 1% level of significance. State the null and alternate hypothesis. Compute the value of the test statistic: a. z=3.88 b. z=1.42 c. z=3.41 d. t=3.88 e. t=1.42 Which is the correct conclusion: a. reject H0. the weekday workers take longer break b. do not reject H0. the weekday workers take longer break c. reject H0. There is no significant difference between break times of weekday and weekend workers. d. do not reject H0. there is no significant difference between break times of weekday and weekend workers. e. none of the above
Added by Cristian L.
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Step 1:** Null Hypothesis: \(H_0: \mu_1 = \mu_2\) Alternate Hypothesis: \(H_1: \mu_1 > \mu_2\) ** Show more…
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