A college professor wants to estimate the difference in mean…
A college professor wants to estimate the difference in mean test scores of students who have taken his statistics and genetics classes in the past 10 years. He selects a random sample of 20 student records from the statistics course and a random sample of 22 student records from the genetics course. These two samples were independent random samples. The study provided the results shown in the table below. Calculate the pooled estimate of the variance. Statistics Genetics Sample size 20 22 Sample mean 78 75 Sample standard dev. 10 12