Explore BrainMass

# Probability

### Probability of Passing a Spelling and Grammar Test

Using Excel, please demonstrate use of functions to solve the following probability problem. Tired of careless spelling and grammar, a company decides to administer a test to all job applicants. The test consists of 20 sentences. Applicants must state whether each sentence contains any grammar or spelling errors. Half the sen

### Stock Return Calculation using Normal Distribution

Farrell Corporation's common stock is \$25. The price is expected to increase by \$5 over the coming year. The standard deviation of the expected price is \$3. The distribution of the end of year possible price is approximately normal. Determine the probability of earning a return greater than 30 percent over the coming year from

### Normal probability distribution: Errors on tax returns by Dotties Tax Service

Dotties Tax Service specializes in federal tax returns for professional clients, such as physicians, dentists, accountants, and lawyers. A recent audit by the IRS of the returns she prepared indicated that an error was made on 15 percent of the returns she prepared last year. Assuming this rate continues into this year and she p

### Sampling Distribution of Sample Mean: IQ Scores

The population of IQ scores forms a normal distribution with a mean of u=100 and a standard deviation with a mean of sigma=15. What is the probability of obtaining a sample mean greater than m=105 for a random sample of n=9 people? How do I set this problem up, what is the correct formula?

### Probability of 1.5% defective Nokia cell phone antennas

PLEASE SHOW ALL THE WORK 62. Suppose 1.5 percent of the antennas on new Nokia cell phones are defective. For a random sample of 200 antennas, find the probability that: a. None of the antennas is defective. b. Three or more of

### Binomial Probability: Defective Pieces

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 o

### Statistics: Probability that 3 loans will be defaulted for Coast Bank and Trust

Ms. Bergen is a loan officer at Coast Bank and Trust. From her years of experience, she estimates that the probability is .025 that an applicant will not be able to repay his or her installment loan. Last month she made 40 loans. a. What is the probability that 3 loans will be defaulted? b. What is the probability that at le

### 20 Statistics questions: random variable, binomial distribution, Poisson, std deviation

1. A random variable is assigned numerical values based on the outcomes of an experiment - TRUE OR FALSE 2. For a binomial distribution, each trial has a known number of successes. For example, a 4 question multiple choice test can only have zero, one, two, three or four successes TRUE OR FALSE 3. To construct a binomial p

### Hyper Peometric Probability: Defective Television Sets

Kolzak Appliance has just received a shipment of 10 TV sets. Shortly after they were received, the manufacturer called to report that he had inadvertently shipped 3 defective sets. Ms. Kolzak, decided to test 2 of the 10 sets she received. What is the probability that neither of the 2 sets tested is defective? Pls find the pr

### Binomal Situation: Determine the probabilities of x = 1 and x = 2

In a binomal situation n = 5 and pi denotes a binomial population paramenter. Do not confuse it with the mathematical constant 3.1416. Determine the probabilities of the following events using the binomial formula - a. x = 1 and b. x = 2

### Central limit theorem,Sample mean for holding penalties in college football games.

Central limit theorem: Sample mean A study of college football games shows that the number of holding penalties assessed has a mean of 2.2 penalties per game and a standard deviation of 0.9 penalties per game. What is the probability that, for a sample of 40 college games to be played next week, the mean number of holding pe

### Scores on a standardized aptitude test: minimum score to be in the top 25%

The distribution of scores on a standardized aptitude test is approximately normal with a mean of 500 and a standard deviation of 105 . What is the minimum score needed to be in the top 25% on this test? Carry your intermediate computations to at least four decimal places, and round your answer to the nearest integer.

### EMV Problem for Page Engineering

Page Engineering designs and constructs air conditioning and heating (HVAC) systems for hospitals and clinics. Currently the company's staff is overloaded with design work. There is a major design project due in 8 weeks. The penalty for completing the design late is \$14,000 per week, since any delay will cause the facility to

### Decision Tree for sale of artwork of Mill River's ice skaing park

Residents of Mill River have fond memories of ice skating at a local park. An artist has captured the experience in a drawing and is hoping to reproduce it and sell framed copies to current and former residents. He thinks that if the market is good he can sell 400 copies of the elegant version at \$1.25 each. If the market is

### Probability: Visiting Yellowstone Park & Tetons

50 percent of travelers going to visit the Rocky Mountains visit Yellowstone Park, 40 percent visit the Tetons and 35 percent visit both - What do you think the probability a vacationer will visit at least one of these attractions, what do you think a probability .35 is called and are these events mutually exclusive, please e

### Probability that company will not lose any money next quarter

There is a 50 percent chance this company will earn a profit, a 30 percent chance it will break even, and a 20 percent chance it will lose money next quarter- Use the addition rule to file the probability of the company will not lose any money next quarter, and use the complement rule to find the probability rule it will not

### Gender equity experiment: probability to estimate

A company will promote two employees out of a group of six men and three women, what would you say the chances of this experiment if there is particular concern about gender equity and which concept of probability would you use to estimate these probabilities?

### Sample of Licensed Drivers with Speeding Violations

A sample of 2,000 licensed drivers revealed the following number of speeding violations Number Number of drivers 0, 1, 2, 3, 4, 5 or more 1,910, 46, 18, 12, 9, 65 Total 2,000 What kind of experiment is this, what is one possible event, what do you think the pr

### Probability: Hiring Minority Candidates

A company must hire a new CFO and prepares a final list of five candidates - all are equally qualified. Two of the candidates are members of a minority of a minority group. To avoid bias in the selection of the candidate, the company decides to select the president by lottery. What is the probability one of the minority cand

### Probability

62. Suppose 1.5 percent of the antennas on new Nokia cell phones are defective. For a random sample of 200 antennas, find the probability that: a. None of the antennas is defective. b. Three or more of the antennas are defective.

### Probability

38. One-fourth of the residents of the Burning Ridge Estates leave their garage doors open when they are away from home. The local chief of police estimates that 5 percent of the garages with open doors will have something stolen, but only 1 percent of those closed will have something stolen. If a garage is robbed, what is the p

### Standard normal probabilities variable

Standard normal probabilities Let Z be a standard normal random variable. Calculate the following probabilities using the calculator provided. Round your responses to at least three decimal places. P (z > - 0.82) = P (z &#8804; 0.77) = P( -0.81 < z < 1.25) =

### Expectation and variance: sample solution

Let be a random variable with the following probability distribution: Value Value x of X P(X=x) 4 0.30 5 0.05 6 0.20 7 0.30 8 0.10 9 0.05 Find the expectation E(X) and variance of VAR(X) of X

### Four Poisson Distribution Problems

See attached file for clarity. #3. Assume that the number of uninspected cars caught at a state police checkpoint is Poisson distributed with average 2.1 per hour. (a) What is the average number of cars caught in t hours? (b) What are P(no cars caught in 14 hours? (c) P(at least 3 in 1.5 hours); (d) P(at least 1 car caught w

### Outcomes & Event Probability for Genders of Children

Outcomes and event probability Suppose that the genders of the three children of a family are soon to be revealed. An outcome is represented by a string of the sort GBB (meaning the oldest child is a girl, the second oldest is a boy, and the youngest is a boy). The outcomes are listed in the table below. Note that each outcom

### Probability of intersection or union: Age & Marital status

Probability of intersection or union: Word problems Suppose that 51% of the women who gave birth at a certain hospital last year were over 30 years old, and that 39% were unmarried. If 63% of the women were over 30 or unmarried (or both), what is the probability that a woman who gave birth at the hospital was both unmarried

### Statistics: dice, marbles, survey, cards, smoker, tourist, participants

Two sided dice are rolled. What is the probability that the sum of the two numbers on the dice will be 5? A bag contains 2 red marbles, 3 blue marbles and 7 green marbles. If a marble is randomly selected from the bag, what is the probability that it is blue? A case consists of 41 women and 74 men. If a student is rando

### Probability of intersection or union: pizza containing both

Probability of intersection or union: At a certain pizza parlor, 45% of the customer's order a pizza containing onions, 38% of the customer's order a pizza containing sausage, and 79% order a pizza containing onions or sausage (or both). Find the probability that a customer chosen at random will order a pizza containing both

### Die Rolling probability

Die rolling An ordinary (fair) die is a cube with the numbers 1 through 6 on the sides (represented by painted spots). Imagine that such a die is rolled twice in succession and that the face values of the two rolls are added together. This sum is recorded as the outcome of a single trial of a random experiment. Compute t

### If 61% of eligible voters actually did vote, what is the probability the 1002 actually did vote?

In a survey of 1002 people, 701 said that they voted in a recent presidential election. Voting records show that 61% of eligible voters actually did vote. Given that 61% of eligible voters actually did vote, find the probability that among 1002 randomly selected eligible voters actually did vote.