Question

A researcher compares the effectiveness of two different instructional methods for teaching physiology. A sample of 202 students using Method 1 produces a testing average of 78.1. A sample of 194 students using Method 2 produces a testing average of 56.4. Assume that the population standard deviation for Method 1 is 9.22, while the population standard deviation for Method 2 is 6.91. Determine the 99%confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2.

1. Find the point estimate for the true difference between the population means.

2. Calculate the margin of error of a confidence interval for the difference between the two population means. Round your answer to six decimal places.

3. Construct the 99% confidence interval. Round your answers to one decimal place.

Answer 1