According to labor department statistics the average us, Ask an Expert

Statistics

According to Labor Department statistics, the average U.S. work week shortened from 39 hours in the 1950s and early 1960s to 35 hours in the 1990s. Assume the two statistics are based on independent t samples of 2,500 workers each, and the standard deviations are both 2 hours.

a. Test for significance of change.

b. Give a 95% confidence interval for the difference.

View complete question

Statistics and Probability, Statistics

Category:- Statistics and Probability
Reference No.:- M92190972

Have any Question?Write your Review or question?

Related Questions in Statistics and Probability

Transaction costs you would like to purchase one class a

Transaction costs You would like to purchase on?e Class A share of Berkshire Hath-away through your Scottrade brokerage account. Scottrade charges a $7 commission for online trades. You log into your account, check the r ...

The table shows the results of a survey in which 400 adults

The table shows the results of a survey in which 400 adults from the? East, 400 adults from the? South, 400 adults from the? Midwest, and 400 adults from the West were asked if traffic congestion is a serious problem. Co ...

A banks loan officer rates applicants for credit the

A banks loan officer rates applicants for credit. The ratings are normally distributed with a mean of 200 and a standard deviation of 50. If an applicant is randomly selected, find the probability of a rating that is bet ...

What is the sample size for studies with moe of -35 and -28

What is the sample size for studies with MOE of +/-3.5% and +/-2.8%, with a confidence level of 95%, sample statistics of 50. Suppose the category population was 7500 (less than 10,000)? Remember the FPC. What would be t ...

Yu obtain a 250000 mortgage loan from bank of

You obtain a $250,000 mortgage loan from Bank of Montreal to buy a house. The mortgage has a 5-year fixed rate of 4%/year (using Canadian mortgage convention), and the amortization period of the mortgage is 20 years. (b) ...

Question 1 many high school students take the ap tests in

Question 1. Many high school students take the AP tests in different subject areas. In 2007, of the 144,796 students who took the biology exam 84,199 of them were female. In that same year,of the 211,693 students who too ...

A potato chip bag filling line is supposed to fill bags

A potato chip bag filling line is supposed to fill bags with 10 ounces of potato chips(by weight). The line exhibits a historical process standard deviation of .8 ounces. If chips bags are filled in lots of 20, make a 95 ...

Confidence intervals ci are one of the simpler forms of

Confidence intervals (CI) are one of the simpler forms of inferential statistics. What does the CI represent? And why does our knowledge of the Central Limit Theorem (CLT) and the empirical rule let us understand why the ...

One hundred twenty-five marine recruits participated in a

One hundred twenty-five marine recruits participated in a study to assess the benefits of a strength training program. Each recruit was given a push-up test at the beginning and end of the program. The change in number o ...

A stocks price fluctuations are approximately normally

A stock's price fluctuations are approximately normally distributed with a mean of $104.50 and a standard deviation of $23.62. You decide to purchase whenever the price reaches its lowest 20% of values. What is the most ...

4,153,160 Questions Asked
13,132 Experts
2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Recent Questions

Ask Statistics and Probability Expert