Question
In: Statistics and Probability
A simple random sample of 60 items resulted in a sample mean of 80. The population...
A simple random sample of 60 items resulted in a sample mean of 80. The population standard deviation is
σ = 5.
(a)
Compute the 95% confidence interval for the population mean. (Round your answers to two decimal places.)
to
(b)
Assume that the same sample mean was obtained from a sample of 120 items. Provide a 95% confidence interval for the population mean. (Round your answers to two decimal places.)
to
Solutions
Expert Solution
a)
95% confidence interval for 
is
- Z *
/ sqrt(n) <
< + Z *
/ sqrt(n)
80 - 1.96 * 5 / sqrt(60) < < 80 + 1.96 * 5
/ sqrt(60)
78.73 < < 81.27
95% CI is ( 78.73 to 81.27 )
b)
95% confidence interval for is
- Z *
/ sqrt(n) <
< + Z *
/ sqrt(n)
80 - 1.96 * 5 / sqrt(120) < < 80 + 1.96 * 5
/ sqrt(120)
79.11 < < 80.89
90% CI is ( 79.11 to 80.89 )
orchestra answered 2 years agoRelated Solutions
A simple random sample of 60 items resulted in a sample mean of 80. The population...
A simple random sample of 60 items resulted in a sample mean of
80. The population standard deviation is
σ = 5.
(a)
Compute the 95% confidence interval for the population mean.
(Round your answers to two decimal places.)
to
(b)
Assume that the same sample mean was obtained from a sample of
120 items. Provide a 95% confidence interval for the population
mean. (Round your answers to two decimal places.)
to
A simple random sample of 60 items resulted in a sample mean of 80. The population...
A simple random sample of 60 items resulted in a sample mean of
80. The population standard deviation is 15.
At 95% confidence, what is the margin of error (to 4
decimals)?
-
What is the standard error of the mean (to 4 decimals)?
-
Which statement should you use to explain the 95% confidence
interval ?
Group of answer choices:
A. We are confident that 95% of population are in the confidence
interval
B. We are 95% confident that...
A simple random sample of 80 items resulted in a sample mean of 60. The population...
A simple random sample of 80 items resulted in a sample mean of
60. The population standard deviation is σ = 5.
a.Compute the 95% confidence interval for the population mean.
(Round your answers to two decimal places.)
____ to ___
b.Assume that the same sample mean was obtained from a sample of
160 items. Provide a 95% confidence interval for the population
mean. (Round your answers to two decimal places.)
___ to ____
c.What is the effect of a...
A simple random sample of 40 items resulted in a sample mean of 80. The population...
A simple random sample of 40 items resulted in a sample mean of
80. The population standard deviation is s=20.
a. Compute the 95% confidence interval for the
population mean. Round your answers to one decimal place.
b. Assume that the same sample mean was
obtained from a sample of 120 items. Provide a 95% confidence
interval for the population mean. Round your answers to two decimal
places.
c. What is the effect of a larger sample size
on the...
A simple random sample of 70 items resulted in a sample mean of 60. The population...
A simple random sample of 70 items resulted in a sample mean of
60. The population standard deviation is σ = 15.
(a) Compute the 95% confidence interval for the population mean.
(Round your answers to two decimal places.)
_________ to _________
(b) Assume that the same sample mean was obtained from a sample
of 140 items. Provide a 95% confidence interval for the population
mean. (Round your answers to two decimal places.)
_________ to _________
(c) What is the...
A simple random sample of 60 items resulted in a sample mean of 65. The population...
A simple random sample of 60 items resulted in a sample mean of
65. The population standard deviation is 16. a. Compute the 95%
confidence interval for the population mean (to 1 decimal). ( , )
b. Assume that the same sample mean was obtained from a sample of
120 items. Provide a 95% confidence interval for the population
mean (to 2 decimals). ( , ) c. What is the effect of a larger
sample size on the margin of...
A simple random sample of 60 items resulted in a sample mean of 65. The population...
A simple random sample of 60 items resulted in a sample mean of
65. The population standard deviation is 16. a. Compute the 95%
confidence interval for the population mean (to 1 decimal). ( , )
b. Assume that the same sample mean was obtained from a sample of
120 items. Provide a 95% confidence interval for the population
mean (to 2 decimals). ( , ) c. What is the effect of a larger
sample size on the margin of...
A simple random sample of 60 items resulted in a sample mean of 95. The population...
A simple random sample of 60 items resulted in a sample mean of
95. The population standard deviation is 13.
a. Compute the 95% confidence interval for the population mean
(to 1 decimal).
( , )
b. Assume that the same sample mean was obtained from a sample
of 120 items. Provide a 95% confidence interval for the population
mean (to 2 decimals).
( , )
c. What is the effect of a larger sample size on the margin of
error?
SelectIt increasesIt decreasesIt...
A simple random sample of 60 items resulted in a sample mean of 10. The population...
A simple random sample of 60 items resulted in a sample mean of
10. The population standard deviation is 20.
Compute the 95% confidence interval for the population mean.
Round to 1 decimal place.
Assume that the same sample mean was obtained from a sample of
120 items. Provide a 95% confidence interval for the population
mean. Round to 2 decimal places.
What is the effect of a larger sample size on the interval
estimate? Larger sample provides a larger...
A simple random sample of 60 items resulted in a sample mean of 63. The population...
A simple random sample of 60 items resulted in a sample mean of
63. The population standard deviation is 12.
a. Compute the 95% confidence interval for the population mean
(to 1 decimal).
( , )
b. Assume that the same sample mean was obtained from a sample
of 120 items. Provide a 95% confidence interval for the population
mean (to 2 decimals).
( , )
ADVERTISEMENT
ADVERTISEMENT
Latest Questions
- 3) You are rolling a 12 sided die 8 times. a) What is the size for...
- explain the difference between quantitative and qualitative research strategies. Provide an example of a crime based...
- use postorder and inorder tree traversals to make preorder traversal. #!/usr/bin/env python3 # encoding: UTF-8 """Turning...
- 1. Write an if-else statement to describe an object. Print "Balloon" if isBalloon is true and...
- An investor is considering purchasing a Treasury bond with a 20 year maturity, an 8% coupon...
- Write a program that copies the contents of one file to a destination file. This program...
- how to conduct a marketing mix for 3d crest white strips
ADVERTISEMENT