A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less than that of decaffeinated-coffee drinkers. Assume the population standard deviation for those drinking regular coffee is 1.45 cups per day and 1.56 cups per day for those drinking decaffeinated coffee. A random sample of 47 regular-coffee drinkers showed a mean of 4.42 cups per day. A sample of 37 decaffeinated-coffee drinkers showed a mean of 4.93 cups per day. Use the 0.025 significance level. Is this a one-tailed or a two-tailed test? One-tailed test. Two-tailed test. State the decision rule. (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.) Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round your answer to 2 decimal places.) What is the p-value? What is your decision regarding H0? Do not reject H0. Reject H0.
Answer:
A coffee manufacturer is interested in whether the mean daily consumption of regular-coffee drinkers is less...
Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the day shift. The mean number of units produced by a sample of 51 day-shift workers was 331. The mean number of units produced by a sample of 56 night-shift workers was 337. Assume the population standard deviation of the number of units produced on the day shift is 20 and 27 on the...
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Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the day shift. The mean number of units produced by a sample of 52 day-shift workers was 327. The mean number of units produced by a sample of 58 night-shift workers was 332. Assume the population standard deviation of the number of units produced on the day shift is 23 and 31 on the...
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