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find the mean and standard deviation

The below table lists the last digits of the 73 published distances (in feet) of the 73 home runs hit by Barry Bonds in 2001 when he set the record for the most home runs in a season (based on data form USA today) The last digit of a data set can sometimes be used to determine whether the data have been measured or simply report


Express the indicated degree of likelihood as a probability value. *"it will definitely turn dark tonight." a. 0.5 b. 1 c. 0.30 d. 0.67 *Which of the following can not be a probability? a. 1 b. 0 c. -1 d. 2 *Answer the question,considering t

Quantitative Methods: Finding Probability

Potato chip are sold in 12 oz bags. The bag weights are expected to be normally distributed about this standard. If the standard deviation of the bags is 0.58 oz would it be unusual to find a bag containing 11 oz. The Frito Lay CEO wants to know if it will be unusual for a bag to be 10% or more short.

Quantitative Methods - should a plane go commercial probability

Management is considering going live with a new product that research believes is promising. Engineering estimates that if a $300,000 pilot plant is build there is a 0.75 chance of a high yield versus the alternative of a low yield. If the pilot plant shows a high yield they believe there is a probability of 0.8 that the comm

Poisson Distribution

The number of false alarms a building fire alarm system registers has a Poisson distribution with a mean of 6 false alarms per year. The variance of the number of false alarms is what?

Waiter's Probability for Commission

John has two jobs. For daytime work at a jewelry store he is paid $200 per month plus a commission. His monthly commission is normally distributed with a mean of $600 and a standard deviation of $40. At night he works as a waiter, for which his monthly income is normally distributed with a mean of $100 and a standard deviation o

Normal approximation to the binomial distribution

A. Tossing a Coin Simulate 6 independent tosses of a fair coin. Repeat the procedure to get 200 sets of 6 coin tosses. (That's 1200 total tosses.) List the results. Explain carefully your method of simulating the tosses, whether it involves a computer, a table of random digits, or even flipping several coins at once. Addre

Standard distribution

Assume that the population of heights of male college students is approximately normally distributed with mean m of 68 inches and standard deviation s of 3.75 inches. A random sample of 16 heights is obtained. d. Find the mean and standard error of the xbar distribution. e. Find P (xbar > 70) f. Find P ( xbar < 67) I kno

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 and Discrete Random Variable

1. Let A and B be two events. Suppose that P(A) = 0.2, P(B) = 0.5 and P(B|A) = 0.6. What is the probability of A or B or both occurring? 2. Let A and B be two events. Suppose that P(A) = 0.2, P(B) = 0.5 and P(B|A) = 0.5. What is the probability of A occurring given that B occurs? 3. A common problem facing many old

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?

Binomial Probability

Use the data from a test of Nicorette the table as follows: Mouth or throat soreness No mouth or throat soreness Nicorette 43 109 Placebo 35 118 If two different subjects are randomly selected with replacement, find the probability that they are both from the placebo group. Sow the work.

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

Probability Normal Distribution using z statistic

At a local high school, 1,000 juniors and seniors recently took an aptitude test. The results of the exam were normally distributed with a mean of 250 and a standard deviation of 15. Find a)% of students scoring less than 225 b)number of students that scored less than 180 c)probability of a student selected at random having

Probabilities with Joint Distribution

Using the joint distribution for two RVs X and Y given by F_XY(x,y) = u(x)u(y)[l-e^(-ax)-e^(-ay)+e^(-a(x+y))] and assuming a = 0.5 in each case, find the probabilities: a) P {X </= 1, y </= 2} B) P {0.5 < X < 1.5} C) P {-1.5 < X </= 2, 1 < Y /= 3}

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 problems: 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