Share
Explore BrainMass

Standard Deviation

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

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

Statistics - Variation and Standard Deviation

A population of scores has μ = 20 and σ = 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

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

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.]

68-95-99.7 rule

What is 68-95-99.7 rule? To get a better feel for this concept, give me an example of it from around the home.

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?

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

Simple Variance Calculation

The variance of a population having a standard deviation of 3 is ____. Could you please help me I'm stuck on this one. Please explain how to come up with the solution. Thanks

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

Electrical Resistors

I really need help with this problem. Thank you! A certain machine makes electrical resistors having a mean resistance of 40 ohms and a standard deviation of 2 ohms. What is the probability that a random sample of 50 resistors has a combined resistance of more than 2010 ohms?

Hal recently accepted a sales position with (IBM) selling "big iron"

Hal recently accepted a sales position with (IBM) selling "big iron" (mainframe computers). He has to decide between taking a salary only or taking a smaller salary plus commissions on sales. As part of his decision-making process, he has collected historical data from previous years on the number of mainframe sales made by in

Advanced Statistics Problems

1. Suppose you have invested only in two stocks, A and B. The returns on the two stocks depend on the following three states of the economy, which are equally likely to happen: State of Return on Return on Economy Stock A (%) Stock B (%) Bear

Statistics Concept for health maintenance organizations

4. A random sample of 100 light bulbs is selected. Sixty were found to burn for more than 1,000 hours. Develop a 90 percent confidence interval for the proportion of bulbs that will burn more than 1,000 hours. 5. A health maintenance organization (HMO) wants to estimate the mean length of a hospital stay. How large a sample

A. Fill in the missing values in the table. b. Is the stock of Firm A correctly priced according to the capital-asset-pricing model (CAPM)? What about the stock of Firm B? Firm C? If these securities are not correctly priced, what is your investment recommendation for someone with a well-diversified portfolio?

You have been provided the following data on the securities of three firms, the market portfolio, and the risk-free asset: Security Expected Return Standard Deviation Correlation Beta Firm A 0.13 0.12 ? 0.9 Firm B 0.16 ? 0.4 1.1 Firm C 0.25 0.24 0.75 ? The market portfolio (S&P5

Reliability, Validity of Results

1. How do you interpret the reliability results for the clerical test and work sample? Are they favorable enough for Phonemin to consider using them "for keeps" in selecting new job applicants? 2. How do you interpret the validity results for the clerical test and work sample? Are they favorable enough for Phonemin to con

Level of Confidence and Sample Size

I'm trying to determine what happens to the sample size if the level of confidence is reduced from 95% to 90% but the allowable error and the standard deviation remain, the same. Should it be increased, decreased, remain the same or none of these.

Compute the z values

The Smith family has twins, Rob and Rachel. Both Rob and Rachel graduated from college two years ago, and each is now earning $50,000 per year. Rachel works in the retail industry, where the mean salary for executives with less than 5 years' experience is $35,000 with a standard deviation of $8,000. Rob is an engineer. The m

Statistics Questions

X1 X2 The participants were randomly assigned to groups 1 and 2 34 45 32 35 15 32 27 28 20 34 1. t = 2. df = 3. For a ONE TAILED TEST, with p < .05, what is the Tabled Value, and is the above t significant or not significan

Payback Period to Implement New Product

A business currently has a business intelligence tool called WebFocus in a production environment (supporting end users). Cost to maintain WebFocus is $313,832 per year in software maintenance fees and other associated costs to include helpdesk support and other labor. The business wants to migrate from WebFocus to Oracle D

A manufacturing process involved in the production of plastic molds for a specific automotive application is under study. To control the mean thickness of this (normally distributed) process with a standard deviation, s = 3.0, chart is used with n = 5, LCL = 14.15, and UCL = 15.85.

[1] A manufacturing process involved in the production of plastic molds for a specific automotive application is under study. To control the mean thickness of this (normally distributed) process with a standard deviation, s = 3.0, chart is used with n = 5, LCL = 14.15, and UCL = 15.85. If the process means shifts to 15.2, find t