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Probability of Defective Items from a Sample

A carton of 6 batteries contains 2 that are defective and 4 that are good. If we select 3 batteries at random form this carton, what is the probability that the sample contains exactly 1 defective battery? a) 33.3% b) 50.0% c) 60.0%


Suppose that a telemarketer calls a random sample of 12 households in a community in the night that 80% of the households have someone at home. Find the probability that the person doing the calling finds someone at home in exactly 10 households. a) 10.0% b) 28.3% c) 80.0% Find the mean of the above distribution. a)

Queuing Theory in a Barber Shop

A small barber shop has a single chair and an area for waiting, where only one person can be in the chair at a time, and no one leaves without getting their hair cut. So the system is roughly: Entrance Wait Haircut Exit Assume customers arrive at the rate of 10 per hour and stay an average of 0.5 hour. What is the average

Statistics: Relationship between students and credit cards

See tables in attached file. 1. (TCO 4) What is the probability that the student is a sophomore given he doesn't carry a credit card? 2. (TCO 4) Some students were asked if they carry a credit card. Here are the responses. What is the probability that the student didn't carry a credit card?

Loglinearand logit models

Find a loglinear model that describes this data well. Interpret associations then treating whether killed as the response, find an equivalent logit model. Interpret the effects. See attachment

General Statistics

13) We use the General Rule of Multiplication to combine A. Events that total more than 1.00. B. Events based on subjective probabilities C. Mutually exclusive events. D. Events that are not independent. 14) Which of the following is a correct statement about a probability? A. It may be greater than

Interpreting a Normal Distribiution of two different brands of soft drink

See attached file. You plan to conduct a marketing experiment in which students are to taste one of two different brands of soft drink. Their task is to identify the brand tasted. You select a random sample of 200 students and assume that the students have no ability to distinguish between the two brands. (Hint: if an individ

Resource: Statistical Techniques in Business & Economics

An internal study by the Technology Services 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 P.M. and

Binomial Probability: Arrival of Northwest Airlines

Assume the likelihood that any flight on Northwest Airlines arrives within 15 minutes of the scheduled time is .90. We select four flights from yesterday for study. 1. What is the likelihood all four of the selected flights arrived within 15 minutes of the scheduled time? 2. What is the likelihood that none of the selected f

Binomial Probability for Automobile Parts Estimated to be Defective

A machine that manufactures automobile parts is estimated to produce defective parts 5% of the time. If this estimate is correct, and 9 parts produced by this machine are randomly selected, what is the probability that at most 2 turn out to be defective? Round your answer to four decimal places.

Finding standard deviation and probability: Example questions

1. Population mean = 19.1 15% of data 22.6 Find standard deviation. 2. Population mean 120 Standard deviation 5.7 What is the probability an individual between 120 and 121.3? 3. Population mean 120 Standard deviation 5.3 Sample n =30 Find probability that the sample mean is between 120 and 121.8. 4. Theatre has

Computing Probabilities for Ground Coffee Amounts Spent

In a recent year, about two-thirds of U.S. households purchased ground coffee. Consider the annual ground coffee expenditures for households purchasing ground coffee, assuming that these expenditures are approximately normally distributed as a normal random variable with a mean of $45.16 and a standard deviation of $10.00. 1.

Acceptance-rejection sampling on unit disc

Suppose that the random variables X and Y are independent and uniform on the interval [-1, 1]. You form a random variable Z by sampling from X and Y and computing X^2 + Y^2. Whenever X^2 + Y^2 > 1 the sample is rejected, otherwise it is accepted. Prove that Z is uniformly distributed on [0, 1].

Standard deviation of probability distribution for temperature

Suppose the probability distribution for the high temp in Nevada on June 1 is normally distributed with a mean of 65 degrees. If a box plot was made it would have an IQR = 20 degrees. 1. What's the standard deviation of that probability distribution? I know the answer is 20 / 1.35 - where do you come up with the 1.35?

Probabilty that none watched any of the three sports last year

A survey of a group's viewing habits over the last year revealed the following information: 1. 28% watched gymnastics 2. 29% watched baseball 3. 19% watched soccer 4. 14% watched gymnastics and baseball 5. 12% watched baseball and soccer 6. 10% watched gymnastics and soccer 7. 8% watched all three sports Calcula

Statistics: Problems and Solutions

1.FREQUENCY DISTRIBUTION & DESCRIPTIVE STATISTICS: Open the CUMBA.xls file, which contains data from a random sample of 100 employees at Mock Company Inc. Create a Frequency Distribution of the YEARS OF EXPERIENCE for the employees using intervals of 0-4, 4-8, 8-12, 12-16 and 16-20. Also create the Descriptive Statistics for

Binomial distribution and probability of Bill selling three more cars this month

Bill must sell three more cars this month to meet his quota. Tonigh he has after-dinner appointments with five prospective customers, each of whom happens to be interested in a different car. If he has a %30 chance of success with each customer, what is the probability that he'll meet his quota by tomorrow morning? Suppose that

Compute Probabilities: Airline Passengers Arrive in Several Time Periods

Airline passengers arrive randomly and independently at the passenger-screening facility at a major international airport. The mean arrival rate is 10 passengers per minute. Compute the probability of no arrivals in a 1 minute period. Compute the probability that 3 or fewer passengers arrive in a 1 minute period. Compute t

Solving a Binomial Distribution Problem

Bill must sell three more cars this month to meet his quota. Tonight he has after-dinner appointments with five prospective customers, each of whom happens to be interested in a different car. If he has a %30 chance of success with each customer, what is the probability that he'll meet his quota by tomorrow morning? Suppose that

Random Variables to Measure Level of Interest in a New Product

A company is conducting a survey of 235 people to measure the level of interest in a new product. Assume that the probability of a randomly selected person's being "very interested" is 0.88 and that people are selected independently of one another. a. Find the standard deviation of the percentage who will be found by the surv

Probability: Problems and Solutions

1. A cooler contains 100 cans of soda covered by ice. There are 30 cans of cola, 40 cans of orange soda, 10 cans of ginger ale, and 20 cans of root beer. The cans are all the same size and shape. If one can is selected at random from the cooler, determine the probability that the soda selected will be cola or orange. 2. Brain

Decision Tree Analysis

Tech is playing state in the last conference game of the season. Tech is trailing state 21 to 14, with 7 seconds left in the game, when Tech scores a touchdown. Still trailing 21 to 20, tech can either go for 2 points and win or go for 1 point to send the game into overtime. The conference championship will be determined by t

Decision payoff table for sale of Christmas greeting cards.

6. The manager of the greeting card section of Mazey's department store is considering her order for a particular line of Christmas Cards. The cost of each box of cards is 3.00; each box will be sold for 5.00 during the Christmas season. After Christmas, the cards will be sold for 2.00 a box. The card section manager believe

Decision Analysis

Miramar Co. is going to introduce one of three new products: a widget, a hummer, or a nimnot. The market conditions (favorable, stable, or unfavorable) will determine the profit or loss the company realizes as shown in the following payoff table: Product favorable (0.2) Stable (0.7) Unfavorable (0.1) Widge

Various Aspects of Decision Analysis

5. A payoff table (profits) is shown below: States of Nature Decisions S1 S2 S3 D1 10 8 6 D2 14 15 2 D3 7 8 9 a. Using the maximax criterion, what decision should be made by the decision maker? b. Using the maximin criterion, what decision should be made by the decision maker? c. Using an equal likel

Probability: Binomial and Normal Distribution

3. A new county hospital is attempting to determine whether it needs to add a particular specialist to its staff. Five percent of the general hospital population in the county contracts the illness the specialist would treat. If 12 patients check into the hospital in a day, what is the probability that 4 or more will have the i