Find a 90% confidence interval for the average time to graduation of all students

Calculus For The Life Sciences
2nd Edition
ISBN:9780321964038
Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Publisher:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Chapter13: Probability And Calculus
Section13.2: Expected Value And Variance Of Continuous Random Variables
Problem 10E
icon
Related questions
Question

A university administration claims that its students graduate on average in 4.2 years. A newspaper believes the average time to graduation is higher and polls 81 recent graduates at random. The average time to graduation for the sample is 4.4 years, with a sample standard deviation of 0.5 years.

Find a 90% confidence interval for the average time to graduation of all students.

Expert Solution
steps

Step by step

Solved in 2 steps

Blurred answer
Recommended textbooks for you
Calculus For The Life Sciences
Calculus For The Life Sciences
Calculus
ISBN:
9780321964038
Author:
GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.
Publisher:
Pearson Addison Wesley,