These are statistics questions, I hope I have it in the right place.   Please help!   1. What condition(s) must exist for the...

These are statistics questions, I hope I have it in the right place.

Please help!

1. What condition(s) must exist for the Central Limit Theorem to be valid? List all that apply. 

•n is tolerably high. By most accounts, n > 30

2. When can any one or more of a population’s parameters be known exactly without consulting a sampling distribution or performing a census of the whole population? 

__________________________________________________________ (5 pts) 

3. What population distribution shape will NOT give a normal sampling distribution if the sample n is above 30? 

___________ (5 pts) 

A number of students completed a questionnaire about eating disorders, from which a “Fear of Negative Evaluations”(FNE) was produced. The higher the score, the greater the fear of negative evaluation. Suppose the FNEs of the population of bulimic students have a distribution with mean = 18 and standard deviation of 5. Consider a random sample of 45 students with bulimia. 

4.What is the probability that the sample mean FNE score is greater than 17.5? 

___________ (5 pts) 

5.A distribution of survival data for the reliability of electronics has a unique shape. What is it?  

______________________ (5 pts) 

6. Consider the following conditional probability tree. What is P(A  B)? 

7. If the mean of a sampling distribution is 22.75, and with a standard error of the mean of 5, what is the mean of the original, sampled, population?  

___________ (5 pts) 

8.A given population has a standard deviation of 10. In a sampling distribution of n = 36, what is the standard error of the mean?  

___________ (5 pts) 

9.Given a confidence level of 95%, calculate the confidence coefficient. 

___________ (5 pts) 

10.What happens to the standard error of the mean as n increases? 

___________ (5 pts) 

11. A manufacturer wants to know how big a sample to take from a lot of stamped parts, to estimate the population mean to within .5 sampling error with 90% confidence. Previous studies of this machine indicate that the standard deviation of lengths produced is about 2 mm.  

___________ (10 pts) 

12. A survey was given to 10 randomly selected football fans, asking how much they thought the average football fan spent on food at a football game. The results show that the sample mean and standard deviation were $52.00 and $17.50, respectively. Create a 95% confidence interval for µ. 

___________ (10 pts) 

13. The US Postal Service was evaluated to determine the percentage of mail delivered on time. In a sample of 332,000 mailed items, it was determined that 282,200 items were delivered on time. From this information, determine with 99% confidence the true percentage of items delivered on time.  

___________ (10 pts) 

14. When making golf tees, a manufacturer tries to maintain a weight of .251 ounces per tee. To check whether a molding machine is consistent, 40 tees were randomly sampled from a production run and their weights were calculated into the following statistical printout: 

Variable N Mean SD 

Weight 40 .2525 .002303 

Construct a 99% confidence interval for µ. 

___________ (10 pts) 

15. The FDA publishes the amount of nicotine in commercially available cigarettes. The mean value of all cigarettes in a given year is 22.5 milligrams, with a standard deviation of 2.5 milligrams. A new cigarette is coming on the market, with a mean from a sample of 9 (n = 9) of 26.4 milligrams, and a standard deviation of 2.0 milligrams. Construct a 90% confidence interval for µ for the new cigarette.