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# Probability

### Probability Calculations and Unemployement

Please help with the following problems. Provide step by step calculations. A recently published study shows that a country's true unemployment rate to be 12%. Assume that 300 members of the labour force are selected at random. A) What is the expected number of people unemployed? B) What is the probability that exactly 29

### Probability: Coin Toss

The "at most" and "at least" topic confuses me Could you briefly describe both and post a small example to help explain each?

### Binomial Probability Distribution

The Complaints Department of a popular used car dealer receives most complaints about the electrical system, particularly the starter. The department sent questionnaires to 300 owners of two-year-old, used, full-sized vehicles. The survey showed 15% of the owners had trouble with the starter. Based on the result of the survey, w

### Binomial Probability Distribution Problems

Please help with the following problems. The manager of the local Tim Horton's found that 60% of her employees call in sick on Fridays before the long weekend. Out of a sample of ten employees, what is the probability that: A) exactly three employees will call in sick B) not more than one employee will call in sick. C)

### Probability Calculations- Probability distribution, Expected value

Please help with the following problems. Harvard University published the age profile of it's first time students. A random sample of 33 students has ten students in their thirties, fifteen students in their forties, five students in their fifties, and three students in their sixties. A student is selected randomly from the

### Stats Case Study - Airlines, Flights

A major airline has tracked its on-time status during the past year for flights originating in San Francisco and Los Angeles. The following table reflects the data for 400 flights (see attachment for table). a. How would you determine, based on these data, what is the probability that a flight from one of the two cities will

### Statistics

J&G Painting has hired you as a consultant. You have been gathering data on its painting speed in an effort to help the company be more accurate in submitting bids. Based on data gathered after considering washing, taping, painting, and clean up, one person can paint an average of 100 square feet of indoor wall space per hour (b

### Combination probability

A bridge hand consists of 13 cards dealt at random from an ordinary deck of 52 playing cards. a)How many possible bridge hands are there? b) Find the probability of being dealt a bridge hand that contains exactly two of four aces. c) Find the probability of being dealt an 8-4-1 distribution, that is, eight cards of one suit,

### Probability questions- Independent events

Jill wants to do her MBA in Statistics at a B.C. university. She applies to two universities that offer post-graduate degrees in Statistics. Assume that the acceptance rate at University A is 25% and at University B is 35%. Further assume that acceptance at the two universities are independant events. A) What is the probability

### Anita's, a fast-food chain specializing in hot dogs and garlic fries.

Anita's, a fast-food chain specializing in hot dogs and garlic fries, keeps track of the proportion of its customers who decide to eat in the restaurant (as opposed to ordering the food "to go") so it can make decisions regarding the possible construction of in-store play areas, the attendance of its mascot Sammy at the franchis

### How to set up simulated dice rolling in Excel.

I have to create a simulation in Excel or Crystal Ball (an Excel add-in)only; no other software choices. The task is to simulate a roll of a PAIR of dice--each die having equal probabilities of outcomes: 1, 2, 3, 4, 5 or 6. Perform 50 trials of this simulation. What is the expected value of the dice roll (minimum value

### Binomial distribution: finding the mean and standard deviation

Not all visitors to a certain company's website are customers or potential customers. In fact, the company's executives estimate that about of all visitors to the website are looking for other websites. Assume that this estimate is correct and that a random sample of visitors to the website is taken. a. Estimate the number

### Calculate the Expectation and Variance

Please see the attached file for full problem description. Let X be a random variable with the following probability distribution. Value x of X P(X = x) 0 0.5 10 0.55 20 0.05 30 0.10 40 0.10

### Random variable

Let X be a random variable with the following probability distribution

### A Discussion On E(X) and Var(X) of X

Let x be a random variable with the following probability distribution: Value x of X......P(X = x) ........-1...............0.05 .........0...............0.05 .........1...............0.60 .........2...............0.05 .........3...............0.15 .........4...............0.10 Find the expectation E(X) an

### A man tosses a fair coin 10 times...

A man tosses a fair coin 10 times. What is the probability that he gets at most head? Round your answer to four decimal places.

### Probability - students in a college class

Please see the attached file for full problem description. --- Suppose that a certain college class contains students. Of these, are freshmen, are physics majors, and are neither. A student is selected at random from the class. a. What is the probability that the student is both a freshman and a physics major? b. Sup

### Probability

Please see the attached file for full problem description. --- Suppose that a certain college class contains students. Of these, are sophomores, are chemistry majors, and are neither. A student is selected at random from the class. a. What is the probability that the student is both a sophomore and a chemistry major?

### Probabilities: Senior or Business Major

Suppose that a certain college class contains 59 students. Of these, 35 are seniors, 30 are business majors, and 12 are neither. A student is selected at random from the class. a. What is the probability that the student is both a senior and a business major? b. Suppose that we are given the additional information that the s

### Probabilities: Random Selection Problems

Please help with the following problems. Provide step by step calculations. At a certain college, 51% of the students are female and 17% of the students major in civil engineering. Furthermore, 10% of the students both are female and major in civil engineering. a. What is the probability that a randomly selected female stu

### The probability of union and intersection of independent events

Suppose that A and B are independent events such that P(A) = 0.20 and P(B complement) = 0.70. Find the probability of the intersection of A and B Find the probability of the union of A and B

### Using EXCEL for Standard Normal Distribution Probabilities

Please see the attached file for the full problem description. Let Z be a standard normal random variable. Use a calculator to determine the value of c such that: P (c <= Z <= 1.24) = 0.8533 Carry your intermediate computations to at least four decimal places. Round your answer to at least two decimal places.

### Statistics Control charts, probabilities

This is for Quality Control Consider the xbar chart for the piston-ring example as follows, let ring diameter be normally distributed, and the sample size is n = 5. a) Find the two-sigma control limits for this chart. b) Suppose it was suggested that the two-sigma limits be used instead of the typical three-sigma limits.

### Normal Random Variable

Please label your answers in bold and away from any calculations.. Note: I cannot read .xls files. I could only view .doc files. Let be a standard normal random variable. Calculate the following probabilities. Round your responses to at least three decimal places. a. P {Z > 2.10} = b. P {Z is less than or equal to 1.93}

### Mutually exclusive and independant events

Please see the attachment for the question. Let B and C be two events such that P(B) = 0.50 and P(C) = 0.05. a. Determine P(B U C), given that B and C are mutually exclusive. b. Determine P(B U C), given that B and C are independent.

### Probability

Suppose that A and B are independent events such that P(A)=0.30 and P(B)=0.40. Find the following probabilities... (see attachment for full question)

### The solution gives an intuitive approach to probability problems involving dice. The technique is illustrated by calculating probabilities for the game of "craps".

A popular dice game, called "craps," is played in the following manner. A player starts by rolling two dice. If the result is a 7 or 11, the player wins. If the result is 2, 3, or 12, the player loses. For any other sum appearing on the dice, the player continues to roll the dice until that outcome reoccurs (in which case th

### Probability distribution function

Please see the attached file for full problem description with all proper "X" symbols. --- Can you show me how to complete this kind of problem? Suppose that the genders of the three children of a certain family are soon to be revealed. Outcomes are thus triples of "girls" ( ) and "boys" ( ), which we write , , etc. For ea

### Normal distribution, probabilities (3 problems)

Problem 1 We know the IQ of people is normally distributed with mean 120 and standard deviation (SD) of 25. Calculate the probability that an adult will have a ) IQ less than 100 b) IQ greater than 150 c) IQ between 100 and 150 d) Any person with a score over 200 is considered a genius. In a population of 10000

### Explanation of odds ratio in a study of smoking.

Those who have quit smoking often return to the habit. The authors of a paper concluded that forbidding smoking in the smoker's residence was a significant predictor of the ability to abstain from smoking. They collected data, calculated statistics, and presented the following as support for their conclusion: OR=1.95 C.I.