Can anyone help me in my statistics homework? i need to submit this at 7:59pm

Problem 1Claim: The average electricity bill is less than $120.Z-value: -2.0Significance level (α): 0.01Test type: The claim uses the phrase "less than," which indicates a left-tailed test.Critical value: For a left-tailed test with α = 0.01, the critical z-value is -2.33.Decision: Since the z-value (-2.0) is greater than the critical value (-2.33), it does not fall in the rejection region. Therefore, we fail to reject the null hypothesis.Sentence: Since this is a left-tailed test and the z-value falls in the non-rejection region, we fail to reject the null hypothesis.Problem 2Claim: The average age of voters is more than 35 years.Z-value: 2.10Significance level (α): 0.05Test type: The claim uses the phrase "more than," which indicates a right-tailed test.Critical value: For a right-tailed test with α = 0.05, the critical z-value is 1.645.Decision: Since the z-value (2.10) is greater than the critical value (1.645), it falls in the rejection region. Therefore, we reject the null hypothesis.Sentence: Since this is a right-tailed test and the z-value falls in the rejection region, we reject the null hypothesis.Problem 3Claim: The average monthly internet bill is not equal to $60.Z-value: 2.10Significance level (α): 0.05Test type: The claim uses the phrase "not equal to," which indicates a two-tailed test.Critical value: For a two-tailed test with α = 0.05, we split the significance level in half (0.025 for each tail). The critical z-values are ±1.96.Decision: Since the z-value (2.10) is greater than the positive critical value (1.96), it falls in the rejection region. Therefore, we reject the null hypothesis.Sentence: Since this is a two-tailed test and the z-value falls in the rejection region, we reject the null hypothesis.

Answered by Sefton | 2025-08-23