Confidence Interval and Margin of Error

If a confidence interval for a population mean is (40, 60), what is the sample mean?

• 10

• 100

• 50

• 80

• Not enough information to determine.

If a confidence interval for a population mean is (40, 60), what is the margin of error?

• 10

• 100

• 50

• 80

• Not enough information to determine.

• 1.64

• 1.96

• 2.33

• 2.58

• 1.645

• 1.96

• 2.33

• 2.58

• 1.645

• 1.96

• 2.33

• 2.575

If the margin of error in a confidence interval is 8 and the sample mean is 200, what is the lower bound of the confidence interval?

• 192

• 196

• 200

• 208

If the margin of error in a confidence interval is 8 and the sample mean is 200, what is the upper bound of the confidence interval?

• 192

• 196

• 200

• 208

If the confidence interval for a population mean is (20, 40), what is the sample mean?

• 20

• 30

• 40

• 50

If the confidence interval for a population mean is (20, 40), what is the margin of error?

• 20

• 30

• 40

• 10

A confidence interval for a population mean is calculated as (150, 210). What is the margin of error?

• 30

• 60

• 180

• 360