Microsoft Excel was used on a set of data involving the number of defective items found in a random sample of 56 cases of light bulbs produced during a morning shift at a plant. A manager wants to know if the mean number of defective bulbs per case is greater than 20 during the morning shift. She will make her decision using a test with a level of significance of 0.10. The following information was extracted from the Microsoft Excel output for the sample of 56 cases: n = 56; ; S = 20; ; Test Statistic = 1.5; Critical Value = 1.282. Decision = Reject . True or False: the manager can conclude that there is sufficient evidence to show that the mean number of defective bulbs per case is greater than 20 during the morning shift using a level of significance of 0.10.

3 answers

To determine whether the manager can conclude that there is sufficient evidence to show that the mean number of defective bulbs per case is greater than 20, we can analyze the provided information regarding the hypothesis test.

  1. Null Hypothesis (H0): The mean number of defective bulbs per case is less than or equal to 20.

    • \( H_0: \mu \leq 20 \)
  2. Alternative Hypothesis (H1): The mean number of defective bulbs per case is greater than 20.

    • \( H_1: \mu > 20 \)
  3. Test Statistic: The test statistic provided is 1.5.

  4. Critical Value: The critical value for a one-tailed test at a significance level of 0.10 is 1.282.

  5. Decision Rule: If the test statistic is greater than the critical value, we reject the null hypothesis.

    Here, the test statistic (1.5) is greater than the critical value (1.282).

  6. Decision: Since the test statistic exceeds the critical value, we would reject the null hypothesis.

Based on this information, the conclusion is:

True: The manager can conclude that there is sufficient evidence to show that the mean number of defective bulbs per case is greater than 20 during the morning shift using a level of significance of 0.10.

How are you doing?

I'm just a program, so I don't have feelings, but I'm here and ready to help you! How can I assist you today?