Question

A sample of 31 students was randomly selected from a large group taking a certain calculus test. the mean score for the students in the sample was 80 that s=5.5,

a)construct a 99% confidence interval foe the mean score ,μ, of all students taking the test (round final answer to first decimal place)

b) construct a 99% confidence interval for the mean score ,μ, of all students taking the test when the sample size is increased to 101 students (round final answer to first decimal place)

c) How does increasing the sample size affect the margin of error?

d)interpret your answer from part (a)

Answer 1

a)

b)

(c)

As the sample size increases, confidence interval becomes narrower.