At South High School, 37% of the teachers are between 22 and 30 years old, 25% are between 31 and 40 years old, 31% are between 41 and 50, and 7% are between 51 and 60. Create a probability distribution
of the ages of teachers at South High School, then find the mean age. (Use midpoints of the age ranges).

The survey of study habits and attitudes (ssha) is a psychological test that measures the motivation, attitude toward school, and study habits of students, scores range from 0 to 200. the mean score for u. s. college students is about 115, and the standard deviation is about 30. a teacher who suspects that older students have better attitudes toward school gives the ssha to 55 students who are at least 30 years of age. the mean score is 113.2. assume the population standard deviation is 30 for older students what is the margin of error for a 95% confidence interval for the population mean score for a. older students? b. compute the 95% confidence interval for the population mean score for older students. c. compute the 99% confidence interval for the population mean score for older students. d. compute the 88% confidence interval for the population mean score for older students.