Explore BrainMass
Share

# Standard Deviation

### Dispersion of Two Distributions for Vinyl Washers and Boilers

A plumbing supplier's mean monthly demand for vinyl washers is 24,212 with a standard deviation of 6,053. The mean monthly demand for steam boilers is 6.8 with a standard deviation of 1.7. Compare the dispersion of these distributions. Which demand pattern has more relative variation? Explain.

### Statistics

A set of final examination grades in an introductory quantitative analysis course is normally distributed, with a mean of 73 and a standard deviation of 8. a) What is the probability of getting a grade below 91 on this exam? b) What is the probability that a student scored between 65 and 89? c) The probability is

### Statistics - Standard Deviation.

According to the U.S. Bureau of census current Construction TReport, the average price of a new mobile home in the western part of the United States during 1993 was \$40,500. Assume the standard deviation was \$8,500/ Should a mobile home selling for \$75,000 be considered and outlier? Explain why or why not.

### Standard Deviation for University Grades

The grade point average of the students at BLK is 2.80 with a standard deviation of 0.84. The grade point average of students at SJK is 2.4 with a standard deviation of 0.84. Which university shows a more relative dispersed grade distribution? Explain why?

### Standard Deviation: Piggy Bank would like to examine the required sample size needed to be able to estimate the mean dollars that each card holder will spend each month....

Piggy Bank would like to examine the required sample size needed to be able to estimate the mean dollars that each card holder will spend each month. It would like to be within plus or minus \$10 of the true mean with a 98% confidence level. The standard deviation is thought to be \$500. How many card holders should be sampled? Af

### Sample Standard Deviation for Automobile Manufacturer

An automobile manufacturer has a new model that they claim gets 27 miles per gallon. A consumer testing agency selects 50 of these cars and finds that the sample mean is 25 miles per gallon and the sample standard deviation (s) is 3 miles per gallon. Using a = 0.05 test the manufacturer's claim.

### Standard Deviation

Using an excel spreadsheet and the stdav function calculate the following data and answer the following questions nunderneath The data I choose to observe was how long I spent doing dishes over a 10-day period. Friday, day 1 - 12 minutes. Saturday, day 2 - 19 minutes. Sunday, day 3 - 22 minutes. Monday, day 4 - 0. Tu

### Normally distributed Base Salary for Brand Managers

According to Salary Wizard, the average base salary for a brand manager in Houston, Texas is \$88,592 and the average base salary for a brand manager is Los Angeles, California, is \$97,417. assume salaries are approximately normally distributed, that the standard deviation for brand managers in Houston is \$19,900, and that the

### Find the standard deviation of the data

The number of homicides in Vermont from 1992 through 2001 is given in the following table. Year Homicide Victims 1992 21 1993 15 1994 5 1995 13 1996 11 1997 9 1998 12 1999 17 2000 12 2001 11 b. Find the standard deviation of the data. c. What percent of the data is within 1 standard deviation of the mean?

### Plants Satisfying Demand

You have been offered a position as General Manager of a television manufacturing facility by XYZ Corporation. You have a choice of Plant A or Plant B. At the present time both plants are satisfying their demand for a particular TV (Model FX32) by providing 3200 sets per day on the average. -However, Plant A has a standard

### T and Z Statistics and Pooling

Please help with the following problem. A) When does the t-statistic approximate the z-statistic? Please ask yourself this question before answering: for a probability level of 0.975 on a one-tailed probability distribution, what is z-score and what is t-statistic? Then ask yourself, when does the t-statistic approximates

### Calculate the expected rate of return and standard deviation of return to Learning Tower of Pita shareholders. Who would view the stock of Learning Tower of Pita as a risk reducing investment - the owner of a gambling casino or a successful bankruptcy lawyer? Explain.

1) Scenario Analysis. The common stock of Leaning Tower of Pita, Inc., a restaurant chain, will generate the following payoffs to investors next year: Dividend Stock Price Boom \$5 \$195 Normal economy

### Standard Deviation of SAT Scores

According to the data from the College Entrance Examination Board, scores on the SAT-I test have a mean of 1017, and Q1 is 880. The scores have a distribution that is approximately normal. Find the standard deviation, then use that result to find P99.

### Empercial relation ship

Juan Salvador just completed a study of the life expectancy of 100 light bulbs and discovered that the mean time that they lasted before burning out was 1,900 hours. If the standard deviation was 150 hours, the empirical rule allows Juan to conclude that approximately 68 of the bulbs burned out between _________ and _________ ho

### Standard Deviation

Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the afternoon shift than on the day shift. A sample of 54 day-shift workers showed that the mean number of units produced was 345, with a standard deviation of 21. A sample of 60 afternoon-shift workers sh

### Statistics - Variation and Standard Deviation

A population of scores has &#956; = 20 and &#963; = 5. If every score in the population is multiplied by 2, then the new values for the mean and standard deviation would be: standard deviation = _______________ A sample of scores has M = 30 and s = 10. If 3 points are added to every score in the population, then the n

### The weights of items produced by a company are normally distributed with a mean of 4.5 ounces and a standard deviation of 0.3 ounces.

The weights of items produced by a company are normally distributed with a mean of 4.5 ounces and a standard deviation of 0.3 ounces. a. What is the probability that a randomly selected item from the production will weigh at least 4.14 ounces? Look at attachement too!!! I think I did this all wrong can you help me out

### Decision Making Casino Blues

The new Lucky Lady Casino wants to increase revenue by providing buses that can transport gamblers from other cities. Research shows that these gamblers tend to be older, they tend to play slot machines only, and they have losses with a mean of \$182 and a standard deviation of \$105. The buses carry 35 gamblers per trip. The c

### Calculating the Mean, Median, and Standard Deviation

1) The American Automobile Association checks prices of gasoline before many holiday weekends. Listed below are the self-service prices for a sample of 15 retail outlets during Labor Day weekend of 2007 in the Detroit, Michigan area. 3.44 3.42 3.35 3.39 3.49 3.49 3.41 3.46 3.41 3.49 3.45 3.48 3

### Normally distributed population of heights of 10,000 women

Please answer True or False and explain why 1. For a normally distributed population of heights of 10,000 women, µ= 63 inches and ó = 5 inches. The number of heights in the population that fall between 66 and 68 inches is 1156. 2. In a normal distribution, approximately 91.31% of the area under the curve is found to

### Mean, Standard Deviation

1.What does it mean for a sample to have a standard deviation of zero? Describe the scores in such a sample. 2. A population has mean, M =100 and standard deviation, s = 20. If you select a single score from this population, on the average, how close would it be to the population mean? Explain answer.

### Bank of America's Consumer Spending Survey collected data on annual credit card charges in seven different categories of expenditures: transportation, groceries, dining out, household expenses, home furnishings, apparel, and entertainment ... {See the atached Question File.]

Bank of America's Consumer Spending Survey collected data on annual credit card charges in seven different categories of expenditures: transportation, groceries, dining out, household expenses, home furnishings, apparel, and entertainment ... {See the atached Question File.]

### Reorder point: The annual demand for a product is 15,600 units. The weekly demand is 300 units with a standard deviation of 90 units. The cost to place an order is \$31.20, and the time from ordering to receipt is four weeks. The annual inventory carrying cost is \$0.10 per unit. a. Find the reorder point necessary to provide a 98 percent service probability. b. Suppose the production manager is asked to reduce the safety stock of this item by 50 percent. If she does so, what will the new service probability be?

The annual demand for a product is 15,600 units. The weekly demand is 300 units with a standard deviation of 90 units. The cost to place an order is \$31.20, and the time from ordering to receipt is four weeks. The annual inventory carrying cost is \$0.10 per unit. a. Find the reorder point necessary to provide a 98 percent ser

### Six Sigma - What it means

Please clarify this statement: If you look at the probability of attaining 6 sigma (2 parts per billion), what does this say when the .400 batting average is at least 6 sigma from the mean?

### Samples for a Population of 70

If the standard deviation of a population is 70 and we want the standard error (the standard deviation of the sample mean) to be 14, what is the number of samples that we need to take?

### QUESTION: Suppose that the distribution is bell shaped. According to the empirical rule, approxiamtelty 99.7 % of the relative increases in stock price lie between ? and ?.

There is some evidence that, in the years , a simple name change resulted in a short-term increase in the price of certain business firms' stocks (relative to the prices of similar stocks). (See D. Horsky and P. Swyngedouw, "Does it pay to change your company's name? A stock market perspective," Marketing Science v., pp. .)

### Mean, Standard Deviation, Shape of Distribution

On the midnight shift, the number of patients with head trauma in an emergency room has the probability distribution shown below. (a) Calculate the mean and standard deviation. (b) Describe the shape of this distribution. x 0 1 2 3 4 5 Total P(x) .05 .30 .25

### Capabilities and Adjustments for Packaging Process

The Crunchy Potato Chip Company sells chips in boxes with a net weight of 30 ounces per box(850 grams). Each box contains ten individual 3-ounce packets of chips. Product design specifications call for the packet-filling process average to be set at 86.0 grams so that the average net weight per box will be 860 grams. Specificati

### Clark Heter is an industrial engineer at Lyons products.

Clark Heter is an industrial engineer at Lyons products. He would kike to determine weather there are more units produced on the afternoon shift than on the day shift a sample of 54 day shift workers showed that the mean number of units produce was 345 with a standard deviation of 21. A sample of 60 afternoon shift workers showe

### Useful Life of a Radial Tire

The useful life of a radial tire is normally distributed with a mean of 30,000 miles and a standard deviation of 5000 miles. The company makes 10,000 tires a month. a. About how many tires will last between 25,000 and 35,000 miles? b. About how many tires will last more that 40,000 miles? c. About how many tires will