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Statistics and probabilities

Workers are subject to work-related injuries. One disorder, caused by strains to the hands and wrists, is called carpal tunnel syndrome. It strikes as many as 23,000 workers per year. The U.S. Labor Department estimates that the average cost of this disorder to employers and insurers is approximately $30,000 per injured worker.

Normal Approximation to Binomial Distribution: Retirement Income

Of the total population of American households, including older Americans and perhaps some not so old, 17.3% receive retirement income. In a random sample of 120 households, what is the probability that greater than 20 households but less than 35 households receive a retirement income?

Parallel Reliability

A product is made up of two subsystems in parallel. Subsystem one consists of ten elements in series each with a failure rate of 1/100. The second subsystem consists of 5 elements in series each with a failure rate of 1/200. What is the overall reliability of the system?


The funds dispensed at the atm machine located near the checkout line at the krogers in union, kentucky, follow a normal probability distribution with a mean of $4,200 a day and a standard deviation of $720 a day. The machine is programmed to notify the local bank if the amount dispensed is very low ( less an $2,500) or very hig


According to accountemps inc. 48% of all executives believe that employees are most productive on Tuesdays. a random sample of 200 executives is taken for a study. a. what is the shape, mean, and standard deviation of the sampling distribution of the sample proportion for samples of 200? b. what is the probability that the

Normal approximation for binomial distribution

h-p is said to be the leading seller of pc's in the U.S WITH 27% share of the pc market. if a researcher selects 130 recent pc purchases, use the normal approximation to the binomial to find the probability that more than 39 bought a h-p computer

Quantitative Analysis - Decision Theory Question

Problem 10-14 BMW is planning to launch a new sport utility vehicle (SUV), Initially it will have limited production for this model, with a total of only 20,000 units being produced for the year. King's BMW has been offered up to four of the SUV's for sale. King's estimates that the profit it earns from purchasing these SUV's

Statistics Probability Problem

I am not sure how to compile the contingency table from probabilities given. Each yr ratings are compiled concerning the performance of new cars during the first 90 days of use. Suppose that the other cars have been categorized according to whether the car needs warranty - related repair (yes or no) and the country in which t

Standard Deviation Mean Probability

Many retail stores offer their own credit cards. At the time of the credit application the customer is given a 10 percent discount on the purchase. The time required for the credit application process follows a uniform distribution with the times ranging from 4 minutes to 10 minutes. a. What is the mean time for the applic

3 Probability Homework Problems

I need assistance with problems: 6.51, 6.52 and 6.53 in the attached document. Please use excel. 6.51 All the major stock market indexes posted heavy losses in 2008. The mean one year return for stocks in the S&P 500, a group of 500 very large companies, was -38.5%. The mean one-year return for the NASDAQ, a group of 3200

Computing probability based on a binomial random variable

Thank you for your help on the other questions. Your work was easily understood. Here are two questions that I need help on. 1) LaDonna asks a question in class 4 days out of 5 and Jason asks a question in class 1 day out of 5. What is the probability that one of them will ask a question in class on any given day? (Coul

Probability that a lobster will choose tunnel

A lobster is placed in a tank in which it is given the choice of four tunnels (a, b, c, or d) to travel through. At the opposite end of each tunnel is a cage housing 1 of four types of food. The experiment is conducted 7 separate times and the lobster chooses tunnel 'a' in 5 of the 7 trials. What is the probability that the

probability of 11/11/11

This is not an academic problem per say, but your website was recommended to me for figuring out the statistical significance of my niece turning 11 y/o on 11/11/11 (November 11, 2011) at 11:11 am. I presume that such a birthday can only occur once a century for November 11th to fall on the 11th year of a century ... but how

Deterministic Probability calculations

A toy company is conducting a research for two new exciting products (Zing-Go and Moto-bots). A survey was conducted using 150 children to determine how well each product was perceived by the group The data was organized in the contingency table shown below. Favorable Neutral Unfavorable Total Zing-Go 3

Binomial Probability for Random Selection

A multiple - choice test has 30 questions and each one has five possible answers, of which one is correct. If all answers were guesses, find the probability of getting exactly four correct answers. =

Probabilty likelihood that troubles can be repaired

An important part of the customer service responsibility of a cable company relates to the spread with which trouble in service can be repaired. Historically, the data show that the likelihood is 0.75 that troubles in a residential service can be repaired on the same day. For the first five troubles reported on a given d

Binomial Distribution and Random Selection of Error

Your company's internal auditor believes that 10% of the company's invoices contain errors. To check invoices are randomly selected and 5 are found to have errors. What is the probability that of the 20 invoices written,five more would contain errors if the theory is valid? =

Binomial Probability: Random Selection.

In a report on high school graduation, it was stated that 85% of high school students graduate. Suppose 3 high school students are randomly selected from different schools. What is the probability that all will graduate?

Probability of acceptance

Joe is considering pursuing an MBA degree. He has applied to two different universities. The acceptance rate for applicants with similar qualifications is 25% for University A and 40% for University B. What is the probability that Joe will not be accepted at either university? =

Binomial probability of gender and type of job

Employees of a local university have been classified according to gender and job type. Gender Job Male (M) Female (F) Faculty (FA) 110 10 Salaried staff (SS) 30 50 Hourly Staff (HS) 60 40 If an hourly employee is selected at random what is th

Binomial random variable for large department chain

1.Suppose that 10 percent of all the new steel-belted radial tires shipped to a large department chain store are defective. Find the probability that in a shipment of 30 such tires: a. At most two are defective. b. At least two are defective. 2.Surveys show that 40% of all convenience

Statistics: Mean, the Variance, and the Standard Deviation

Determine the mean, the variance, and the standard deviation of the following discrete distribution. x P(x) 0 .103 1 .118 2 .246 3 .229 4 .138 5 .094 6 .071 7 .001 According to a recent survey, the probability that a passenger files a complaint with the Depar

At Penn State, 60% of the students are from the south

1. At Penn State, 60% of the students are from the southern part of the U.S. 30% are from the north, and the remaining 10% are from another country. All students must take and pass an Entry Level physiology test test. 60% of the southerners have passed the physiology test, 70% of the northerners have passed the test, and 90% o

Probability distribution and intervals

2. A system uses one of two networks to send binary information, where only one of those networks is used to send all bits of a single block of 5 bits. When network 1 is used the probability of an error in one bit is 0.1 and when network 2 is used the probability of error in one bit is 0.3. The probability of an error in using

Poisson Probability Distribution

Phone calls arrive at the rate of 48 per hour at the reservation desk for Regional Airways. Assume that the distributions of arrivals can be approximated by the Poisson probability distribution. (hint: make sure you know Ã?µ for each question). Determine the probability of receiving at most three calls in a five-minute inte

Probability and Randomness: Parts a Million

As a quality engineer working on the Parts a Million production line, you have determined that the probability of producing a defective part is 6%. You want to develop a plan to monitor the quality of this line. Your idea is to take a sample of 20 parts every hour and determine the number of defectives. How many defectives do yo