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Probability ...

It has been reported that the average US office worker receives 14 fax messages per day. For purposes of this exercise, we will assume that the daily number of fax messages is normally distributed with a standard deviation of 5.0 messages. For an office in which 10 workers are employed and considering these person as a simple


For a random variable that is normally distributed, with u = 200 and o = 20, determine the probability that a simple random sample of 4 items will have a mean that is: a. greater than 210 b. between 190 and 230 c. less than 225

Probability of randomly selecting ping-pong ball

The diameter of ping-pong balls manufactures at a large factory is expected to be approximately normally distributed with a mean of 1.30 inches and a standard deviation of 0.04 inch. What is the probability that a randomly selected Ping-pong ball will have a diameter between 1.31 and 1.33 inches? a. 0.0987 b. 0.1747 c. 0.2

Type of probability distribution

What type of probability distribution will most likely be used to analyze the number of chocolate chip parts per cookie in the following problem? The quality control manager of Marilyn's Cookies is inspecting a batch of chocolate chip cookies. When the production process is in control, the average number of chocolate chip pa

Normal distributions: Z scores and probabilities

A continuous random variable, x, is normally distributed with a mean of $1000 and a standard deviation of $100. Convert each of the following x values into its corresponding z-score. a. x = $1000 b. x = $750 c. x = $1100 d. x = $950 e. x = $1225 2.Using the standard normal table, find the following probabilities

Statistics - Probability of Business Failures

The following data represent x = the total number of business and y = the number of business failures in mountain states over a 1-year period. x = Number of y = Number of State businesses business failures Arizona 146.67

Finding probabilities with the help of binomial distribution

A regional manager visits local fast-food franchises and evaluates the speed of the service. If the manager receives her meal within 45 seconds, the server is given a free movie-admission coupon. If it takes more than 45 seconds, the server receives nothing. Throughout the company's franchises, the probability is 0.60 that a

Simulation Model

Problem #19 Customers arrive at the Blinkies Donut shop between 6:30am and 8:30am according to a Poisson process with a mean rate of one every minute. Seventy percent of the arriving customers purchase one or two donuts, while 30% purchase the Blinkies Dozen pack. For customers purchasing one or two donuts, the service time

Utility Analysis

Need help with the attached excel spreadsheet. Sheet 1 is problem, Sheet 2 is template I need to use. Pharmgen Corporation has developed a new medication for the treatment of high blood pressure. Tests on laboratory animals have been promising, and the firm is ready to embark on human trials in order to gain approval from t

Understanding statistics: probabilities of observing events.

1. Assume that company A makes 80% of all electrocardiograph machines, company B make 15% of them, and the company C makes the other 5%. The electrocardiographs machines made by company A have a 4% rate of defects, the company B machines have a 5% rate of defects, while the company C machines have a 8% rate of defects. a) If a

Statistics: understanding z-scores and probabilities of observing events.

I would like some help with the following problems. Can I please get the actual manual work for the problems so I can follow the formula and follow the steps with other word problems. Thanks. 1. A normal population has a mean of 20.0 and a standard deviation of 4.0. a. compute the z value associated with 25.0. b. what prop

calculating probabilities of events

The Dept. of Labor has reported that 30% of the 2.1 million mathematical and computer scientists in the United States are women. If 3 individuals are randomly selected from this occupational group, and x = the number of females, determine P(x = 0), P(x = 1), P(x - 2), and P(x = 3).

A probability problem: computing expected values and decision making ...

There is a probability that the river will flood next year. Riverside's profits for the coming year depend on whether Laura buys the flood insurance and whether the river floods. The profits (which take into consideration the $10,000 premium for the flood insurance) for the four possible combinations of Laura's choice and river

Probability ... (Please see the attached file)

1. The number of homicides in Vermont from 1992 through 2001 is given in the following table. Find the mean, median, and mode of the data. 2. Find the standard deviation for the data shown in the table of problem #6.3. Use your answer from problems #6 and #7 to answer the following questions: a. What percent of the data i

Probability Distributions

Compose an email to discuss the following: Begin your email to AIU by first providing an overview of the database, i.e. a story. Be sure to include information about how you would use the concept of probabilities to apply to profiles for hiring more satisfied individuals. (Job Satisfaction is an attitude about one's j

Probability problem

If a die rolled one time, classical probability would indicate that the probability of a "two" should be 1/6. If the die is rolled 60 times and comes up "two" only 9 times, does this suggest that the die is "loaded"? Why or why not? It is reported that about 35% of adults attend sports event during the previous year. W


60 million households with personal computers were distributed as shown here with regard to geographic location and access to the internet. What is the probability that a randomly selected computer household would be in the category described by (South or Midwest or Yes)? In the category (West and No)? Access Northea

Statistics Probability of the Coeffcient

Long-term history has shown that 65% of all elected offices in a rural county have been won by Republican candidates. This year there are 5 offices up for public election in the county Let r be the number of public offices won by Republicans. a) Find P(r) for r=0,1,2,3,4, and 5 b) Make a histogram for the r probability d

Probability of Observing an Event

An extended-life light bulb claims the bulb has an average life of 12,000 hours, with a standard deviation of 500 hours. If the distribution is bell shaped and symmetrical, what is the approximate percentage of these bulbs that will last? a. Between 11,000 and 13,000 hours? b. Over 12,500 hours? c. Less than 11,000 hou

Discrete random variables and their probablility distributions

1.Thirty per cent of all patients undergoing a particular diagnostic procedure require a sedative. In a random sample of 10 patients undergoing the procedure, what is the probability that a.at least half will require a sedative? b.fewer then 3 will require a sedative? c.at least 9 will not require a sedative? 2.The durati

Random Variables Classification and Market Age

1.) Random Variables: Classification- Which of the following are continuous variables and which are discrete? a.) Speed of an airplane b.) Age of college professor chosen at random c.) Number of books in the college bookstore d.) Weight of a football player chosen at random e.) Number of lightning strikes in Rock Mountain

Questions with geometric and negative binomials

The solution addresses: The situation for using a geometric random variable occurs when we observe a sequence of independent "trials". Each trial has two possible outcomes which are usually called "success" and "failure".The probability of success is denoted and remains the same from trial to trial. Since each trial only ha

Normal Probability distribution applications

Problem 1) The weigh of a sophisticated running shoe is normally distributed with a mean of 12 ounces and a standard deviation of 0.5 ounces. a) What is the probability that a shoe weighs more than 13 ounces? b) What must the standard deviation of weght be in order for the company to state that 99.9% of its shoes are lea

Arrangement and Group Statistics

3. For the grand opening, an arena has selected 5 finalists, each of whom will win a season ticket located in one of 5 sections: The upper balcony, lower balcony, main floor, courtside, or a luxury box. (5 pts. each) a. How many different arrangements could there be for this promotion? b. The arena is also selecting 6 winne

Probability of Sample proportion

A producer of a juice drink advertises that it contains 10% real fruit juices. A sample of 75 bottles of the drink is analyzed and the percent of real fruit juices is found to be 6.5%. If the true proportion is actually 0.10, what is the probability that the sample percent will be 6.5% or less? a.0.7211 b.0.1562 c.0.5488

Infinite Population with a Mean

Given an infinite population with a mean of 75 and a standard deviation of 12, the probability that the mean of a sample of 36 observations, taken at random from this population, exceeds 78 is a.0.4332 b.0.0668 c.0.0987 d.0.9013

Probability and Odds in Favor of an Event

The odds in favor of an event are the number of successes divided by the number of failures. The probability of this event occurring is the number of successes divided by the sum of the number of successes and the number of failures. The number of successes is five and the number of failures is four. Find the odds in favor

Calculate each probability for smoking by race for males

Refer to the contingency table shown below. (a) Calculate each probability (i-vi) and explain in words what it means. (b) Do you see evidence that smoking and race are not independent? Explain. (c) Do the smoking rates shown here correspond to your experience? (d) Why might public health officials be interested in this type o