Problem

A data set about speed dating includes "like" ratings of male dates made by the female dates. The summary statistics are $n=185, \bar{x}=6.59, s=2.05$. Use a 0.05 significance level to test the claim that the population mean of such ratings is less than 7.00. Assume that a simple random sample has been selected. Identify the null and alternative hypotheses, test statistic, Pvalue, and state the final conclusion that addresses the original claim.
Determine the test statistic.
(Round to two decimal places as needed.)

Answer

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Answer

Final Answer: The test statistic is approximately \(\boxed{-2.72}\).

Steps

Step 1 :Identify the null and alternative hypotheses. The null hypothesis (H0) is that the population mean is equal to 7.00, and the alternative hypothesis (H1) is that the population mean is less than 7.00.

Step 2 :Calculate the test statistic using the formula for a one-sample t-test: \(t = (\bar{x} - \mu) / (s / \sqrt{n})\), where \(\bar{x}\) is the sample mean, \(\mu\) is the population mean under the null hypothesis, \(s\) is the sample standard deviation, and \(n\) is the sample size.

Step 3 :Substitute the given values into the formula: \(\bar{x} = 6.59\), \(\mu = 7.00\), \(s = 2.05\), and \(n = 185\).

Step 4 :Calculate the test statistic: \(t = -2.72\). This value is negative, indicating that the sample mean is less than the population mean under the null hypothesis. This is consistent with the alternative hypothesis that the population mean is less than 7.00.

Step 5 :To make a final conclusion, compare the test statistic with the critical value or calculate the P-value.

Step 6 :Final Answer: The test statistic is approximately \(\boxed{-2.72}\).

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