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# Dispersion and Spread of Data

### Casino Odds

A gambler plays roulette, and makes a \$1.00 bet on a pair of numbers, 4000 times. The bet pays 17 to 1 and it covers two numbers. I need to find the chance that the casino will make less than \$300 from these plays. 1. Find the amount of money the casino is expected to make 2. What is the standard error of the sum and the ch

### Graphing and Basic Statistics

Please see the attached for the math questions I need help with. 1. The following table gives the population of certain states according to the 2000 census. State Population Illinois 12,419,293 New Jersey 8,414,350 New York 18,976,457 Tennessee 5,689,283 Texas 20,851,820 Construct a bar graph from this informat

### The length of time to do a complete full service oil choice at Speedy-Lube, is normally distributed with a mean of 15.8 minutes and a standard deviation of 2.2 minutes.

Always get overwhelmed by the amount of material when covered at a comprehensive level. Attached is the study material of what to be prepared to cover at the conclusion of this course. I have worked through them but get stumped at several points. Can you provide a systematic approach to these problems and provide a reference to

### Mean Squares & Population Variance

Answer the following, carrying your intermediate computations to at least three decimal places and rounding your responses to at least one decimal place. A) Given an estimate of this common population variance based on the variance of the sample means given. B) Give an estimate of this common population variance by pooling th

### Expectation and Variance of a Random Variable X

Expectation and variance of a random variable Let X be a random variable with the following probability distribution: Value x of x P(X=x) -30 0.35 -20 0.25 -10 0.05 0 0.30 10 0.05 Find the

### A student's grade on an exam

1) A student's grade on an exam was transformed to a z-value which is negative. therefore, we know that he or she scored: Choices: higher 16% of class, higher than 45% of class, above the first quartile, below the mean, lower than 16% of the class. I think is is the lower than 16% of the class. 2) Which of one of the follow

### Standard Deviations - MacBurger

The MacBurger restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a standard deviation of 1 minute. The quality-assurance department found in a sample of 50 customers at the Warren Road MacBurger that the mean waiting time was 2.75 minutes. At the .05 signi

### Normal distribution - Jon Molnar will graduate from Carolina Forest High School this year.

7-54. Jon Molnar will graduate from Carolina Forest High School this year. He took the American College Test (ACT) for college admission and received a score of 30. The high school principal informed him that only 2 percent of the students taking the exam receive a higher score. The mean score for all students taking the exam is

### Estimating the Population Mean

SEE ECCO INFO ATTACHED The quality manager at Ecco Company, a maker of back-up alarms for use on industrial vehciles such as forklifts, is interested in estimating the mean dollar volume for warranty claims for products made in Boise on the day shift. He has taken a pilot sample. See info attached. a. Assuming that the

### Random Sampling and Error

6.1 Consider the following data to be a population of N=20 values ______________________________________________________________ 5 3 2 6 6 7 3 3 6 7 7 9 7 5 3 12 6 10 7 2 ___________________________

### Standard deviation, mean

A union of restaurant and foodservice workers would like to estimate the mean hourly wage,µ, of foodservice workers in the U.S. The union will choose a random sample of wages and then estimate µ using the mean of the sample. What is the minimum sample size needed in order for the union to be 90% confident that its estimate is

### Confidence Interval and Random Sample

1. A confidence interval for a population mean has a margin of error of 10.7. What is the length of the confidence interval? 2. A random sample of size 17 is taken from a population. A normal probability plot of the sample data is found to be very close to linear. The population standard deviation is unknown. The appropriate m

### Probability and Standard Deviation Questions

1. The time that the customers at the "self serve" check out stations at the Mejers store spend checking out follows a uniform distribution between 0 and 3 minutes. a. Determine the height and draw this uniform distribution. b. How long does the typical customer wait to check out? c. Determine the standard deviation of the

### Probability & Standard Deviation

14. A file cabinet manufacturer estimates that 5% of its file cabinets will have drawers that close improperly. Assume a production run of 120 cabinets is completed. a. What is the mean and standard deviation of this distribution? b. What is the probability that 7 or more are defective? c. What is the probability that exactly

### Computing the Mean and Median Numbers

60. Owens Orchards sells apples in a large bag by weight. A sample of seven bags contained the following numbers of apples: 23, 19, 26, 17, 21, 24, and 22. a. Compute the mean number and median number of apples in a bag. b. Verify that _(X _) _ 0. Describing Data: Numerical Measures 62. The Citizens Banking Company is stu

### Basic Statistical Concepts

1. In words, explain what is measured by each of the a. SS b. Variance c. Standard Deviation 2. A population has u=100 & sigma=20. If you select a single score from this population, on the average, how close would it be to the population mean? Explain your answer 3. Can SS ever have a value less than zero? Explain your

### Studentized and Standardized Version

A variable has a mean of 144 and a standard deviation of 25. Five observations of this variable have a mean of 156 and a sample standard deviation of 16. Determine the observed value of the a. standardized version of x (x with dash over, see attachment) b. studentized version of x (x with a dash over, see attachment).

### Homogeneity of Variance Test in SPSS

1. Using SPSS, check the following data for homogeneity of variance: Group 1 Group 2 Group 3 1 1 1 2 4 8 3 9 18 4 16 32 a) Using an alpha of .05, what can you conclude about homogeneity of variance from the output? Word process your response

### Standard Deviation

The true length of boards cut at a mill with a listed length of 10 feet is normally distributed with a mean of 123 inches and a standard deviation of 1 inch. What proportion of the boards will be over 125 inches in length?

### Calculation of mean and variance of a discrete random variable

1. Suppose that a variable x has the following distribution function: x p(x) 3 0.23 5 0.41 9 0.36 What is the population mean? 2. Suppose that a variable x has the following distribution function: x p(x) 1 0.18 6 0.16 9 0.15 24 0.51 What is F(9)? 3. Suppose that a variable x has th

### Difference of the Standard Deviations of the Treatment Effect

RESEARCHERS at a university conducted experiments with poplar trees. Listed below are weights (kg) of poplar trees given no treatment and poplar trees treated with fertilizer and irrigation. Does there appear to be a difference between the two standard deviations? No treatment: 0.15 0.02 0.16 0.37 0.22 fertilizer and irrig

### What do you think the market shares will be next month?

Over any given month, Dress-Rite loses 10% of its customers to Fashion, Inc., and 20% of its market to Luxury Living. But Fashion, Inc., loses 5% of its market to Dress-Rite and 10% of its market to Luxury Living each month; and Luxury Living loses 5% of its market to Fashion, Inc., and 5% of its market to Dress-Rite. At the p

### Mean and the standard deviation for frequency distribution

Determine the mean and the standard deviation of the following frequency distribution. Class Frequency 0 up to 5 2 5 up to 10 7 10 up to 15 12 15 up to 20 6 20 up to 25 3

### Range, Arithmetic Mean Income, Population Variance, Standard Deviation

The annual incomes of the five vice presidents of TMV Industries are: \$125,000; \$128,000; \$122,000; \$133,000; and \$140,000. Consider this a population. 1. What is the range? 2. What is the arithmetic mean income? 3. What is the population variance? The standard deviation? 4. The annual incomes of officers of another firm

### Probability calculations based on normal probability

1. Suppose that the random variable x is normally distributed with mean = 1,000 and standard deviation = 100. Sketch and find each of the following probabilities: a. P(1,000<_x<_1,200) e. P(x<_700) b. P(x>1,257) f. P(812<_x<_913) c. P(x<1,035) g. P(x>891) d. P(85

### Mean and Standard Deviations

Advertising expenses are significant component of the cost of goods sold. Listed below is a frequency distribution showing the advertising expenditures for 60 manufacturing companies located in the Southwest. Estimate the mean and the standard deviation of advertising expense. See attached file for chart.

### Calculating Sample Size with Confidence Level and Standard Deviation

We want to estimate the population mean within 5, with a 99 percent level of confidence. The population standard deviation is estimated to be 15. How large a sample is required?

### Quartiles, deciles, and various percentiles.

The Thomas Supply Company, Inc. is a distributor of small electrical motors. As with any business, the length of time customers take to pay their invoices is important. Listed below, arranged from smallest to largest, is the time, in days, for a sample of The Thomas Supply Company, Inc. invoices. a. Determine the first and t

### Normal Probability..

Ayrshire cows average 47 pounds of milk a day with a standard deviation of 6 pounds. For Jersey cows the mean daily production is 43 pounds, with a standard deviation of 5 pounds. Assume that normal models describe milk production for these breeds. One farmer has 20 jerseys, while a neighboring farmer has 10 Ayrshires. What'

### Question on Basic Statistics

I need to research the definition of what is called the distribution of a data population. Also, I need to find the statistic that measures the width of dispersion ("looseness" or "tightness") of the population data about its mean.