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Probability of Sample Mean.

QUESTION 4 A manufacturer of power tools claims that the average amount of time required to assemble their top-of-the-line table saw is fifty (50) minutes with a standard deviation of forty (40) minutes (the very large standard deviation is due to a variety of factors including a large variation in skills among the 'Do it yours

Probability of Orders for Installation of Computer Information System

The number of orders for installation of a computer information system arriving at an agency per week is a random variable X with the following probability distribution: X P(x) 0 0.10 1 0.20 2 0.30 3 0.15 4 0.15 5 0.05 6 0.05 a. Prove that P(X) is a probability distribution. b. Find the cumulative distribution

Real Estate: Conflict and Conflict in Selling Houses

A real estate agent has four houses to sell before the end of the month by contracting prospective customers one by one. Each customer has an independent 0.24 probability of buying a house on being contacted by the agent. a. If the agent has enough time to contact only 15 customers, how conflict can she be of selling all fou


1. A z-score of z = +3.00 indicates a location that is ____. A) near the center of the distribution B) slightly above the mean C) far above the mean in the extreme right-hand tail of the distribution D) The location depends on the mean and standard deviation for the distribution. 2. For a distribution of scores, which of th

Probability question

Laptop computers produced by a company have an average life of 38.36 months. Assume that the life of a computer is exponentially distributed (which is a good assumption). a. What is the probability that a computer will fail within 12 months. b. If the company gives a warranty period of 12 months, what proportion of computers

Learning Curve and Process Capability

Based on chapter learning and assuming no relationship between the questions What is process capability? Explain it in context of how it is used in your organization. Also explain, what is the learning curve, and how can it be applied?

Probability of Defective Tires

A shipment of 100 tires from the TruTire Corporation is known to contain 20 defective tires. Ten tires are selected at random and each tire is replaced before the next tire is selected. The probability of getting at most 4 defective tires is ____________. The probability of getting more than 6 defective tires is _________.

Z score for probability calculation

The department of Weston Materials, Inc. manufacturer of demountable carports, indicates that two workers take an average of 32 hours with a standard deviation of two hours to build a garage. Suppose that the times are joining a normal distribution. (Closer to 2 decimal places) 1. Determine the value of z for 29 hours. 2 De

Determination of Various Probabilities with Poisson Distribution

Q2: US Airlines average about 1.2 fatalities per moth. Assume the probability distribution for x, the number of fatalities per month, can be approximated by a poisson probability distribution. a) what is the probability that no fatalities will occur during any given month? b) what is the probability that one fatality will occu

Probability Distributions: Bottled Water

Is the bottled water you're drinking really purified water? A four year study of bottled water brands conducted by the natural resources found that 25% if bottled water is just tap water. Consider a sample of five bottled water brands, and let x equal the number of these brands that use tap. a) Explain why x is (approx.) a bi

Chi square test for binomial distribution

Each,day Monday through Saturday, a baker bakes three large chocolate cakes and those not sold on the same day are given away to a food bank. Use the data shown in the following table to test the 0.05 level of significance whether they may be looked upon as a value of a binomial random variables. # of cakes sold # of days 0 1

Ten questions on statistics.

Questions about statistics (please see attached). 1. The graph shows the results of a survey of drivers who were asked to name the most annoying habit of other drivers. You randomly select six people who participated in the survey and ask each one of them to name the most annoying habit of other drivers. Let x represent the n

Binomial probability problems

A doctor prescribed the drug penicillin to three different patients as a form oLtreatment for an infectious disease. It is known from the general population that 20 out of every 100 individuals are allergic to the drug. . (a) What is the probability that all three patients are allergic to the drug? (b) What is The probability

Poisson Probability

An internal study by the technology service4 department at lahey electronics revealed company employees receive an average of two emails per hour. Assume the arrival of these emails is approximated by the Poisson distribution. 1. What is the probability Linda Lahey, company president, received exactly 1 email between 4 pm and

Detailed Explanation to Statistics - Probability

1. A recent survey conducted by Towers Perrin and published in the Financial Times showed that among 460 organizations in 13 European countries, 93% have bonus plans, 55% have cafeteria-style benefits, and 70% employ home-based workers. If the types of benefits are independent, what is the probability that an organization selec

Computer Languages to Generate Random Numbers

Most computer languages include a function that can be used to generate random numbers. In Excel, the RAND function can be used to generate random numbers between 0 and 1. If we let x denote a random number generated using RAND, then x is a continuous random variable with the following probability density function: f(x) = {1

Estimate / justification

It is difficult to make budgetary projections in the current economic climate. In particular, a decision regarding long-range planning will be made, in part, using the likelihood that the current recession will last less than 1.5 years. To estimate this probability, information from all previous recessions in the United States


Suppose that the national unemployment rate in six months is forecast as 7.4% with an uncertainty of 2.3% (percentage points) as given by the estimated standard deviation of the forecast. Please assume a normal distribution with this mean and standard deviation. ---Find the probability that the unemployment rate will be over

Net Present Value and Measured Risk

A consensus of experts has agreed on the following table of potential NPVs and their likelihoods for a capital budgeting project that involves considerable uncertainty and is therefore risky: PROBABIlITY NPV ($thousands) 0.15 (300) 0.35 (50) 0.45 500 0.05

Probability / conditional probability

In your opinion, the best outcome would be to have the communications contract awarded to your company but to have the construction contract awarded to a different company. This is not because you are fond of your competition, but instead because if you were to win both, the result would place some strain on your (relatively) s

Probability of Real-estate being Sold

Cooper Realty is a small real estate company located in Albany, New York, specializing primarily in residential listings. They recently became interested in determining the liklihood of one of their listings being sold within a certain number of days. An analysis of company sales of 800 homes in previous years produced

Statistics - Value - Probability

1. What value represents the 25th percentile? 2. A normal distribution has a mean of 80 and a standard deviation of 14. Determine the value above which 80% of the values will occur. 3. A normal population has a mean of 75 and a standard deviation of 5. You select a sample of 40. Compute the probability the sample mean is:

A Partnership Between Dude Ranches and Mobile Homes

Dude Ranches Incorporated was founded on the idea that many families in the eastern and southern areas of the United States do not have a sufficient amount of vacation time to drive to the dude ranches in the Southwest and Rocky Mountain areas for their vacations. Various surveys indicated, however, that there was a considerable

Binomial Model: Calculate put price

Please help with the following problem. Include calculations. Suppose that the stock now sells at $80, and the price will go up by 5% or down by 5% at the end of first six month (t = ½). Then, the price will either go up by 10% or down by 10% at the end of year (t = 1). A call option on the stock has an exercise price of

Probability: Expected Profit and Poisson Distribution

1) A contractor is considering a project which he estimates will yield a $160,000 profit with a probability of 65% and a loss of $50,000 with a 35% probability due to poor weather and material issues. What is his expected (value) profit? 2) CSI has a 20 share meaning that while it is being broadcast, 20% of the TV sets are tu

Probability and the Queing Theory

People arrive a a particular sales counter at the rate of 6 in any 15 minute period and are served on a "first come first served" basis. Arrivals occur randomly throughout the hour and the arrival rate is the same during the entire business day. It takes 5 minutes to service a single customer. How likely is it that exactly 1 cus

Probability - research problem

What is an example of a research problem at your organization that would benefit from the use of either descriptive statistics or probability distribution statistics? Explain.

Decision Making and State of Nature

Allen Abbott has a wide-curving, uphill driveway leading to his garage. When ther is a heavy snow, Allen hires a local carpenter, who shovels snow on the side in teh winter, to shovel his driveway. The snow shoveler charges charges $30 to shovel the driveway. Following is a probability distribution of the number of heavy snows e

Discrete Probability Distributions

A Tamiami shearing machine is producing 10 percent defective pieces, which is abnormally high. The quality control engineer has been checking the output by almost continuous sampling since the abnormal condition began. What is the probability that in a sample of 10 pieces: a. Exactly 5 will be defective? b. 5 or more will b

Binomial Distribution Chart - Probability Tree

7. Construct a binomial distribution chart and table showing all of the outcomes if a woman would like to know all possible outcomes of having 3 children. Also show this using a probability tree diagram. a. What are the odds the second child is a boy? b. What are the odds she has all 3 boys?