1. The quality of cotton cloth is a function of the quality of the raw cotton used in its manufacture. One key attribute of raw cotton is the length of the cotton fibers: the longer the better. Suppose a yarn mill buys raw cotton from a cotton gin that produces cotton fiber with a mean length of 1.25 inches and a standard deviat
Assume that a population is normally distributed with a mean of 100 and a standard deviation of 15. Would it be unusual for the mean of a sample of 3 to be 115 or more? Why or why not?
The specifications call for a shaft to be 1.000 inch in diameter. The acceptable tolerances are +/- 0.005 inches. By doing a process study, you have determined that the average output of diameter is 1.002 and the standard deviation is 0.002. What is the probability that a shaft taken at random from the process will need to be re
1. The scores of students on the ACT college entrance examination in a recent year had a normal distribution with a mean of 18.6 and a standard deviation of 5.9. A simple random sample of 60 students who took the exam is selected for study: a) What is the shape, mean(expected value), and standard deviation of the sampling d
View the "Sampling Distribution of the Mean" within a Multimedia Presentation. InteliBoard Assessment 1. The mean of the sampling distribution is equal to a. the population standard deviation b. the sample mean c. the sample standard deviation d. the population mean e. none of the above 2. The standard error of t
The KW water is provided to approximately 750,000 people, who are served through more than 362,000 accounts. All accounts are metered and billed monthly. the probability that an account has an error in a month is 0.001, and accounts can be assumed to be independent. a- what is the mean and standard deviation of the number of ac
For some reason, I have had such difficulty with this type. I do not simply want to know the answers, but I truly want to get how to figure this out before my final exam. Thank you so much for your help. The mean starting salary for college graduates in the spring of 2000 was $31,280. Assume that the distribution of starti
See attached file for formulas and amounts. Question #1 / 5 Let be a standard normal random variable. Use the calculator provided to determine the value of such that . Carry your intermediate computations to at least four decimal places. Round your answer to at least two decimal places. Question #2 / 5 Suppose th
1. If an original set of measurements is made in inches and has a mean of 36 and a variance of 144, what will be the mean, variance, and standard deviation if: a) the unit is changed to feet? b) 6 inches must be added to each measurement to correct an error? c) The measurements are converted to centimeters (2.5 cm = 1 i
Please see the attached question. Pacific Fishing Company is a fish packing company. The company sells cans of salmon with a labeled weight of 213 grams. The quality control engineer reports that the cans actually have a mean weight of 218 grams and a standard deviation of 5 grams. The weights are approximately normally distr
(a) Why is the Normal distribution so important, particularly with respect to problems dealing with statistical inference? (b) Ok, now that we accept/believe that the Normal distribution is so widely applicable, computationally why is it so useful?
The VIX is quoted in terms of percentage points and translates, roughly, to the expected movement in the S&P 500 index over the next 30-day period, on an annualized basis. For example, if the VIX is at 21, this represents an expected annualized change of 21% over the next 30 days; thus one can infer that the index option ma
An apple juice producer buys all his apples from a conglomerate of apple growers in one northwest state. The amount of juice squeezed from each of these apples is known to be normally distributed with a mean of 2.25 ounces and a standard deviation of 0.15 ounce. Between what two values (in ounces) symmetrically distributed a
Please answer the exercise below in Excel and show your work including formulas. A PGA (Professional Golf Association) tournament organizer is attempting to determine whether hole (pin) placement has a significant impact on the average number of strokes for the 13th hole on a given golf course. Historically, the pin has been
Select the correct answer and explain briefly why: 11. The price-to-earnings ratio for firms in a given industry is distributed according to normal distribution. In this industry, a firm with a standard normal variable value of Z=1: A. Has an average price-to-earnings ratio B. Has a below average price-to-earnings ratio C
See attached files. To Satisfy concerns of potential advertisers, the management of OurCampus! has undertaken a research project to learn the amount of time it takes users to download a complex video features page. The marketing department has collected data and has made some claims based on the assertion that the data follo
Please select the correct answer (please write in a few words how you have a arrived at your conclusion) 12. In a statistic class, 10 scores were randomly selected with the following results were obtained (mean=71.5): 74, 73, 77, 77, 71, 68, 65, 77, 67, 66. What is the standard deviation? A. 22.72 B. 12.00 C. 4.77 D. 5
6. A large population of overdue bills has balances that follow a normal curve. When we take a sample of 100 of these the average is $500 and the SD is $100. (a) What statement can you make about the range $300 to $700? (b) What statement can you make about the range $480 to $520? 10. Pollsters try to determine wh
What is a normal distribution? Describe the properties of a normal distribution. Please provide references.
The lifetimes of light bulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 5 hours. What percentage of the bulbs have lifetimes that lie within one standard deviation of the mean on either side? Use the 68-95.99.7 Rule. Please give a through and simplistic explanation in th
I have several questions relate to frequency distribution that I need support. Please see my questions below and please post with examples if you can so I have more understanding. 1. Does it necessarily true that any frequency distribution contains any form of data sample? Please illustrate your answer with examples. 2. C
What is a normal distribution? If you look at a process and can use a tool to normalize the data, or convert it to a normal distribution, how does that benefit the testing to ensure the process is working correctly?
Assume that you own a small factory. A critical piece of machinery in your factory will need to be replaced in 180 days. If the machinery does not show up on time, you will need to shut down until it arrives. This might cause you to permanently lose customers.When you order the part you will need to pay the $500,000 in advance.
1. Ages of applicants for a particular scholarship are normally distributed with a mean age of 21.3 years and a standard deviation of 1.85 years. If an applicant is randomly selected, find the probability that the applicant is under 18 years old. Express answer as a decimal - four decimal places. 2. Song lengths scheduled fo
4. A tool industry publication claims that the average salary for executives is $129,500 and the standard deviation of all salaries in the industry is $13,500, a study of 20 executives finds that the average salary is $136, 700 with a standard deviation of $22,570. (5) Identify: = _________, s = __________, ? = ______
10. According to the empirical rule, if the data form a "bell-shaped" normal distribution, ________ percent of the observation will be contained within 1 (one) standard deviation around the arithmetic mean. (Points: 4) 68.26 75.00 88.89 93.75 11. The probability that a new advertising
The number of days Americans take each year for vacation is normally distributed with a mean of 15.8 days and a standard deviation of 2.2 days. X P(X < x) P(X > x) Mean Std dev 11 .0146 .9854 15.8 2.2 15 .3
The starting salaries of individuals with an MBA degree are normally distributed with a mean of $40,000 and a standard deviation of $5,000. What percentage of MBA's will have starting salaries of $34,000 to $46,000? The weights of items produced by a machine are normally distributed with a mean of 8 ounces and a standard de
Please help with the following problem. A college is located in the geographic center of mainland United States. The admission officer examines the east-west distance of the college from the hometown of each incoming resident student. Incoming resident students living to the east of the college are scored as + distances, and
2.22 Would the data for number of murders by those convicted of the crime be an example of a floor or ceiling effect? 2.36. For each of the types of data described below, would you present individual data values or grouped data when creating a frequency distribution? Explain your anwser clearly. (a) eye color observed for 87