Confidence Interval Review

Question 1

Determine which distribution to use, if any.

Accepted Answer

t-distribution

Question 2

As the sample size increases, the confidence interval gets __________.

Accepted Answer

narrower

Question 3

Determine if this is a means or a proportions problem.

Accepted Answer

Means

Question 4

A confidence interval is the ____________ plus or minus the __________ .

Accepted Answer

Point Estimate, Margin of Error

Question 5

Determine what distribution to use, if any.

Accepted Answer

Neither

Question 6

Find the minimum sample size.

Accepted Answer

34

Question 7

Determine whether or not this is a means problem or a proportions problem.

Accepted Answer

Means

Question 8

Determine the critical value for a 90% confidence interval

Accepted Answer

1.645

Question 9

Determine whether this is a means or a proportions problem.

Accepted Answer

Proportions

Question 10

Identify the Critical value for a 95% confidence interval.

Accepted Answer

2.447

Question 11

Check to see if the conditions are met in order to create a confidence interval.

Accepted Answer

Yes, because np̂ ≥ 5 and nq̂ ≥ 5

Question 12

As the confidence level increases, the confidence interval gets __________.

Accepted Answer

wider

Question 13

Find the minimum sample size needed to have a 4% margin of error with 99% confidence.

Accepted Answer

977

Question 14

Find a 95% confidence interval for the mean.

Accepted Answer

(6510, 7138)

Question 15

Construct a 90% confidence interval for the true proportion.

Accepted Answer

(0.595, 0.645)

Questions 15