Question 58462This question is from textbook
: I seek your help in the form of probability and statistics. Thank you for your help and instruction.
1. The Human Relations Department of Electronics, Inc., would like to include a dental plan as part of the benefits package. The question is:
How much does a typical employee and his or her family spend per year on dental expenses? A sample of 45 employees reveals the mean amount spent last year was $1,820, with a standard deviation of $660.
a. Construct a 95 percent confidence interval for the population mean.
b. The information from part (a) was given to the president of Electronics, Inc. He indicated he could afford $1,700 of dental expenses per employee. Is it possible that the population mean could be $1,700? Justify your answer
2. The Warren County Telephone Company claims in its annual report that “the typical customer spends $60 per month on local and long distance service.” A sample of 12 subscribers revealed the following amounts spent last month.
$64 $66 $64 $66 $59 $62 $67 $61 $64 $58 $54 $66
1. What is the point estimate of the population mean?
2. Develop a 90 percent confidence interval for the population mean
3. Is the company's claim that the “typical customer” spends $60 per month reasonable?
3. In a poll to estimate presidential popularity, each person in a random sample of 1,000 voters was asked to agree with one of the following statements:
1.The President is doing a good job.
2. The President is doing a poor job.
3. I have no opinion.
This question is from textbook
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 1. The Human Relations Department of Electronics, Inc., would like to include a dental plan as part of the benefits package. The question is:
How much does a typical employee and his or her family spend per year on dental expenses? A sample of 45 employees reveals the mean amount spent last year was $1,820, with a standard deviation of $660.
a. Construct a 95 percent confidence interval for the population mean.
x-bar = 1820
E=1.96(660/sqrt(45))=192.838
CI: 1820-192.838<= mu <=1820+192.838
CI: (1627.162,2012.838)
b. The information from part (a) was given to the president of Electronics, Inc. He indicated he could afford $1,700 of dental expenses per employee. Is it possible that the population mean could be $1,700? Justify your answer
Yes, $1700 is in the 95% confidence interval.
-----------------
2. The Warren County Telephone Company claims in its annual report that “the typical customer spends $60 per month on local and long distance service.” A sample of 12 subscribers revealed the following amounts spent last month.
$64 $66 $64 $66 $59 $62 $67 $61 $64 $58 $54 $66
1. What is the point estimate of the population mean?
x-bar = 62.58
2. Develop a 90 percent confidence interval for the population mean
This is a T-Interval with n=12, x-bar=62.58, s=3.9418
(60.54,64.627)
3. Is the company's claim that the “typical customer” spends $60 per month reasonable?
$60 is slightly outside of the CI.
----------------
3. In a poll to estimate presidential popularity, each person in a random sample of 1,000 voters was asked to agree with one of the following statements:
1.The President is doing a good job.
2. The President is doing a poor job.
3. I have no opinion.
What is the question?
Cheers,
Stan H.
|
|
|
