A local church has a congregation consisting of 480 adult members. The church's administrators would like to estimate the average weekly donation per member per week. A random sample of 65 members was found to have an average donation of $50.40 and a standard deviation of $12.30. The 95% confidence interval to estimate the average weekly donation is _______ .

Question

Quizplus · Accepted Answer

The 95% confidence interval is calculated using the formula: mean ± (critical value) * (standard deviation / sqrt(sample size)). Here, the mean is $50.40, the standard deviation is $12.30, and the sample size is 65. Using a t-distribution for 64 degrees of freedom, the critical value is approximately 2.00. The interval is $50.40 ± 2.00 * ($12.30 / sqrt(65)), which results in ($47.56, $53.24).

A Local Church Has a Congregation Consisting of 480 Adult