Final answer:
Annie's study found a marriage rate of about 3.36% among the sampled group, and by conducting a hypothesis test using the 0.10 level of significance, we can determine if this supports her claim that the marriage rate is greater than 2.3%.
Step-by-step explanation:
Annie is concerned about a statistic regarding marriage opportunities for never-previously-wed, university-educated American women over 40. A study claims that the likelihood of such a woman getting married is 2.3%. To refute this, Annie conducts her own research and finds that out of 476 similar women now aged 45, 16 are married. This yields an observed proportion of 16/476, which is about 3.36%. To determine if this evidence supports Annie's claim that the chances are greater than 2.3%, we can perform a hypothesis test.
For the hypothesis test, we will define the null hypothesis (H0) as the probability of marriage being 2.3% (p0 = 0.023) and the alternative hypothesis (H1) as the probability of marriage being greater than 2.3%. Using a 0.10 level of significance, we will calculate the test statistic and the corresponding p-value.
The formula for the test statistic in a proportion hypothesis test is:
z = (p - p0) / sqrt((p0(1 - p0)) / n)
where:
p is the sample proportion,
p0 is the hypothesized population proportion, and
n is the sample size.
Applying the sample data, we can calculate the test statistic and find the p-value using a z-table. If the p-value is less than 0.10, we reject the null hypothesis and conclude that there is evidence to support Annie's claim that the chance of getting married is greater than 2.3%.