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Quantitative Methods

The time between arrivals of cars at the Petroco Service Station is defined by thw following probability distribution. Time Between Arrivals 9min) Probability 1 .15 2 .30

Problems related to probability calculations based on discrete distributions

23. The 2002 New York City Housing and Vacancy Survey showed a total of 59,324 rent-controlled housing units and 236,263 rent-stabilized units built in 1947 or later. For these rental units, the probability distributions for the number of persons living in the unit are given. Number of persons Rent-Controlled

Quantitative Methods for guessing a flat tire

Four students riding to school together offer the excuse of a flat tire on their car for missing a test. On the makeup test, the professor asks the students to each identify the tire that went flat. If they really didn't have a flat tire and randomly select one that supposedly went flat is the probability that they all select


The heights of 18 year old men are approximately normally distributed with mean 68 inches and a SD of 3 inches. A. What is the probability that an 18 year old selected at random is between 67 and 69 inches tall? B. If a random sample of 9 18 year olds men is selected, what is the probability the the mean hight x is be

Probability (Continuous Random Variables)

1. Suppose that a variable x has the following distribution function: f(x) = 0.0800x for x between 0 and 5.0 What is the population mean? 2. Suppose that a variable x has the following distribution function: f(x) = 0.3200x for x between 0 and 2.5 What is the population variance? 3. Suppose that a variable x has the fo

Quantitative Analysis

Given a normal distribution with ? = 100 and ? = 10, what is the probability that: a. X > 75? b. X < 70? c. X > 112? d. 75 < X < 85? e. X < 80 or X > 110? f. 10% of the values are less than what X value? g. 80% of the values are between what two X values (symmetrically distributed around the mean)? h. 70% of the value

Binomial Distribution

I need to show all work such as formula commands. Label the following variables as discrete or continuous and explain why it is so, then verify at least one of the other postings. a. The number of new accounts established by a salesperson in a year. b. The time between customer arrivals to a bank ATM c. The number of

Quantitative Methods and Decision Trees

Kroft Food products is attempting to decide if it should introduce a new line of salad dressings called Special Choices. The company can test-market the salad dressings in selected geographic areas or bypass the test market and introduce the market and introduce the product nationally. The cost of the test market is $150,000. I

standard deviation of cruise ship destinations

I know that each cruise (trip) is 1000 customers, with a standard deviation of 100. But how do I compute the percentages of cruises that take between 950 and 1025. 2. The five percent of cruises that represent the fewest number of passengers take on what number of passengers of less?

Quantitative Analysis - Shopping Preferences

Please see the attached file for full description. A sample of 500 respondents was selected in a large metropolitan area to determine various information concerning consumer behavior. The following contingency table was obtained:

Prepare a report for the customer that presents the expected value in points of each throw of the darts, and then present a graphic representation of at least three plans.

A game company that manufactures a dart game that dispenses tickets has been asked to put a business plan together for a customer who wishes to buy the game. The dart game gives 5 tickets for a score of 50, 4 tickets for a score of 40, 3 tickets for a score of 30, 2 tickets for a score of 20, 1 ticket for a score of 10, and no

Standard deviation and probability.

In 1851 there were 25,466 nurses in Great Britain. Age Range Yrs 20-29 30-39 40-49 50-59 60-69 70-79 80-89 Midpoint X 24.5 34.5 44.5 54.5 64.5 74.5 84.5 Percent of Nurses 5.7 9.7 19.5 29.2 25.0 9.1 1.8 I have three parts to this question that is similar to one I am working on, Please detail how you do this: 1) Find t

Stats Mulyiple choice questions and machine breakdowns

(1) There are 20 questions in a multiple choice test. Each question has five choices and one correct answer of these five choices. A student did not study. He/she answers the questions at random. What are the probability that he/she makes...more than 10 answers right?exactly eight right?at most 7 right? (2)A can company repor

Statistics: probability, standard error, confidence interval

(Part 1) A random sample of 1000 voters are classified as to whether they are in a low, medium, or high income bracket and whether they favor a new tax reform. The observed frequencies are presented in the table. [see attachment] What is the following probability? P(M'|A) (Part 2) Indications are that the average age at

Dr Icit ESP Experiment

1.) Dr. Icit is conducting and ESP experiment. A computer is used to randomly select and present a number one of five pictures (house, boat, shoe, people, or horse). The subject must determine which picture is being presented on the computer screen (being viewed only by the researchers). The researcher records the answers as eit

binominal distribution and probability

Please show all work and some explanation as to why you chose the formula you did. Part 1. In some countries, girls are valued much less than boys. Sometimes women in such countries abort fetuses known to be girls and many girl babies are victims of infanticide. Suppose there are 43 girls to every 57 boys who reach age 1 in

Moment generating functions and limit theorems

Problems on moment generating functions --------------------------------------- 1. Let X and Y be independent normal rv's, each with mean mu and variance sigma^2. Use moment generating functions to show that X+Y and X-Y are independent normal rv's. 2. If X and Y are independent and M_X(t)=exp{2e^t-2} a

Application of binomial probability in waiting time

You are manager of bank and you want to make sure customers do not have an overly long wait for a customer representative (other than the ATM or deposit box which requires no employee interaction). You know historically for each customer there is a X% chance a customer will walk in and will need customer service. You are going t

Are E1 and E2 mutually exclusive? What is the probability of exactly two girls? Find a recurrence relation and initial conditions that generate a sequence that begins with the given term.

Suppose a coin is flipped and a die is rolled. Let E1 denote the event "the coin shows a tail", let E2 denote the event "the dies shows a 3", and let E3 denote the event "the coin shows heads and the die shows an odd number". Are E1 and E2 mutually exclusive? A family of four children. Assume that it is equally probable

Probability Number Questions

(A roulette wheel has 38 numbers: 18 red, 18 black, a 0, and a 00 (0 and 00 are neither red nor black). When the wheel is spun, all numbers are equally likely to be selected.) What is the probability that the wheel lands on 0? A die is loaded so that the numbers 2 through 6 are equally likely to appear, but 1 is three tim

Die, Card and Cash in Hand Game Probabilities

One fair die is rolled. What is the probability of getting an even number? A card is selected at random from an ordinary 52-card deck. What is the probability that it is a heart? In the Maryland Cash In Hand game, to win the grand prize the contestant must match seven distinct numbers, in any order, among the numbers 1 t

Probability Distribution Binomial

Question(1): A university found that 20% of its students withdraw without completing the introductory statistics course. Assume that 20 students registered for the course. a. Compute the probability that two or fewer will withdraw. b. Compute the probability that exactly four will withdraw. c. Compute the probability that

Probability questions: accident rates for drivers in different age groups

An auto insurance agency was investigating accident rates for drivers in different age groups. The following contingency provides a joint probability distribution for drivers by age group and accident rate. a) What is the probability that a randomly selected person from the above group has had more than one accident regardle

Level of data, data descriptions

1. You would like to help some of your math-deficient friends understand probability before they loose too much on lottery tickets. After shuffling two decks of cards, you lay down 40 of them. You say that there should be 10 in each of the four suits: hearts, diamonds, spades, and clubs. What you actually get is 9 hearts, 8 di

Expected Value and Moment Generating Function

1) Type i light bulbs function for a random amount of time having mean mui and standard deviation sigmai, i=1,2. A light bulb randomly chosen from a bin of bulbs is a type 1 bulb with probability p, and type 2 with prob. (1-p). what is the expected value and the variance of the lifetime of this bulb? 2) Mx(t)=exp{2(e^t)-2

IQ Score Distribution

Assume that adults have IQ scores that are normally distributed with a mean of 100 and a standard deviation of 15. Find the probability that a randomly selected adult has an IQ between 110 and 120 (referred to as bright normal)

Probability based on Normal distribution..

Assume that human body temperatures are normally distributed with a mean of 98.20ºF and a standard deviation of 0.62 ºF. a. Bellevue Hopistal in New York uses 100.6ºF as the lowest temperature considered to be a fever. What percentage of normal and healthy persons would be considered to have a fever? Does this percentage