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# Probability

### Find a percentile from a known normal probability distribution

Please help with the following problem. A newspaper article reported that people spend a mean of 6 hours per day watching TV, with a standard deviation of 1.9 hours. A psychologist would like to conduct interviews with the 15% of the population who spend the most time watching TV. She assumes that the daily time people spe

### Quantative Research Methods - 36. An investment will be worth \$1,000, \$2,000, or \$5,000 at the end of the year. The probabilities of these values are .25, .60, and .15, respectively. Determine the mean and variance of the worth of the investment. ... [Please the attached questions file.]

36. An investment will be worth \$1,000, \$2,000, or \$5,000 at the end of the year. The probabilities of these values are .25, .60, and .15, respectively. Determine the mean and variance of the worth of the investment. 39. A Tamiami shearing machine is producing 10 percent defective pieces, which is abnormally high. The qual

### Distribution for the Interest Rate: Home Loan

A recent survey of banks revealed the following distribution for the interest rate being charged on a home loan (based on a 30-year mortgage with a 10% down payment). Interest Rate 7.0% 7.5% 8.0% 8.5% >8.5% Probability 0.12 0.23 0.24 0.35 0.06 If a bank is selected at random from the distribut

### Probability Problem of Big Ten University

An alcohol awareness task force at Big-Ten university sampled 20 students after the midterm to ask them whether they went bar hopping the weekend before the midterm or spent the weekend studying, and whether they did well or poorly on the midterm. The following result was obtained. Did Well on Midterm

### Binomial Distribution

Use the binomial distribution to determine the probability that a student will get at least 8 out of 10 questions on a ten question multiple choice test correct by just guessing if each question has four choices. Assume that the student randomly guesses any of the four choices with a .25 chance of guessing the CORRECT choice.

### Probability - Statistics Replacement

A. Two cards are randomly selected without replacement from a shuffled deck of 52 cards. Find the probability of getting a ten (10) on the first card and a club on the second card. B. An employee needs to call any 1 of 5 colleagues at home. Assume that the five colleagues are random selections from a population in which

### Statistics - Binomial Distribution

Use the binomial distribution to determine the probability that a student will get at least 8 out of 10 questions on a ten question multiple choice test correct by just guessing if each question has four (4) choices. Assume that the student randomly guesses any of the four choices with a .25 chance of guessing the CORRECT choic

### Probability of Unchanged Independent Variables

Suppose we have two stocks, stock A and stock B. Suppose that each stock has the following probabilities of decreasing (D), remaining unchanged (U) and rising (R), and that they are independent. Stock A: P(D)=.2, P(U)=.1 and P(R)=.7 Stock B: P(D)=.3, P(U)=.3 and P(R)=.4 Let X=0,1,2 be the the number of stocks that RIS

### Probability: Calculating the Odds

Question: If a person were to be hit by lightning, they have a 33 percent chance of being killed. (a) Find the odds that a person will be killed if struck by lightning. (b) Find the odds against a person being killed if struck by lightning.

### Probability - If a bill is chosen at random what is the probability that it is either for the Midwest or from the South? Given the bill is from the east what is the probability that it is for a physicians visit? ... [See the attached questions file.]

Refer to table 3B. If a bill is chosen at random what is the probability that it is either for the Midwest or from the South? Given the bill is from the east what is the probability that it is for a physicians visit? ... [See the attached questions file.]

### Normal Probability Plots

Explain the use of normal probability plot to evaluate whether a set of data is normally distributed?

### 1. In previous tests, baseballs were dropped 24 feet onto a concrete surface, and they bounced an average of 92.84 inches ... 2. Use the Poisson distribution to find the indicated probabilities. In one year, there were 116 homicide deaths in Richmond, Virginia. For a randomly selected day, find the probability that the number of homicide deaths is 0. ... [See the attached questions file.]

1. In previous tests, baseballs were dropped 24 feet onto a concrete surface, and they bounced an average of 92.84 inches. In a test sample of 40 new balls, the bounce heights had a mean of 92.67 inches and a standard deviation of 1.79 inches. Use a 0.05 significance level to determine whether there is sufficient evidence to sup

### Probability, Variability, Regression and Statistical Measures

I'm stuck can you help me, please explain your answers. 1) The following payoff table shows profits associated with a set of 3 alternative under 2 possible states of nature. States A1 A2 A3 1 12 -2 8 2 4 10

### Probability - 1. A certain airplane has two independent alternators to provide electrical power. The probability that a given alternator will fail on a 1-hour flight is .02. What is the probability that (a) both will fail? (b) Neither will fail? (c) One or the other will fail? Show all steps carefully. 2. The probability is 1 in 4,000,000 that a single auto trip in the United States will result in a fatality. Over a lifetime, an average U.S. driver takes 50,000 trips. (a) What is the probability of a fatal accident over a lifetime? Explain your reasoning carefully. Hint: Assume independent events. Why might the assumption of independence be violated? (b) Why might a driver be tempted not to use a seat belt "just on this trip"?

Question 1: A certain airplane has two independent alternators to provide electrical power. The probability that a given alternator will fail on a 1-hour flight is .02. What is the probability that (a) both will fail? (b) Neither will fail? (c) One or the other will fail? Show all steps carefully. Question 2: The probabilit

### Probability Distributions - Using our data set from Unit 1, compose an email to the head of the American Intellectual Union which discusses the following: Begin your email to AIU by first providing an overview of the database, i.e. a story. ...

The problem: Using our data set from Unit 1, compose an email to the head of the American Intellectual Union which discusses the following: Begin your email to AIU by first providing an overview of the database, i.e. a story. Be sure to include information about how you would use the concept of probabilities to apply

Assume that the readings on the thermometers are normally distributed with a mean of 0 degrees and a standard deviation of 1 degrees C. A thermometer is randomly selected and tested. Find the probability of a reading that is less than -2.75.

### Probability

Assume that the readings on the thermometers are normally distributed with a mean of 0 degrees and a standard deviation of 1 degrees C. A thermometer is randomly selected and tested. Find the probability of a reading that is between 2.00 and 2.34

### Probability: Mean Weights of Men

Assume that mens weights are normally distributed with a population mean of 172 pounds and a population standard deviation of 29 pounds. If 81 men are randomly selected, find the probability that they have a mean weight between 100 and 165 pounds.

### Probability - Scores for men on the verbal portion of the SAT

Scores for men on the verbal portion of the SAT test are normally distributed with a mean 509 and a standard deviation of 112. Randomly selected men are given the Columbia review course before taking the SAT test. Assume that the course has no effect. If 16 of the men are randomly selected, find the probability that their mea

### Probability - The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. One classic use of the normal distribution is inspired by a letter to dear abby in which a wife claimed to have given birth 308 days after a brief visit from her husband, who was serving in the US Navy. given this information, find the probability of a pregnancy lasting 308 days or longer.

The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. One classic use of the normal distribution is inspired by a letter to dear abby in which a wife claimed to have given birth 308 days after a brief visit from her husband, who was serving in the US Navy. given this i

### Find the probability of an adults IQ score.

Assume that adults have IQ scores that are normally distributed with a mean of 100 and a standard deviation of 15. Find the probability that a randomly selected adult has a IQ between 110 and 120. Find the probability that a randomly selected adult has an IQ less than 135.

### Poisson Distribution - use the Poisson Distribution the indicated probabilities in one year, there were 116 homicide deaths in Richmond VA. For a randomly selected day, find the probability that the number of homicide deaths is 1.

Use the Poisson Distribution the indicated probabilities in one year, there were 116 homicide deaths in Richmond VA. For a randomly selected day, find the probability that the number of homicide deaths is 1.

### Poisson Distribution - Use the Poisson Distribution the indicated probabilities in one year, there were 116 homicide deaths in Richmond VA. For a randomly selected day, find the probability that the number of homicide deaths is zero.

Use the Poisson Distribution the indicated probabilities in one year, there were 116 homicide deaths in Richmond VA. For a randomly selected day, find the probability that the number of homicide deaths is zero.

### Poisson Distribution - Use the Poisson distribution to find the indicated probabilities. Currently, 11 babies are born in the village of West point, population of 760, each year. Find the probability that on a given day, there is at least one birth.

Use the Poisson distribution to find the indicated probabilities. Currently, 11 babies are born in the village of West point, population of 760, each year. Find the probability that on a given day, there is at least one birth.

### Probability - statistics for normally distributed I.Q.'s with mean

Please answer true or false and give reason why. 7. P (-0.5 < Z < -0.3) = 0.0736. 8. For normally distributed I.Q.'s with mean of 100 and standard deviation of 16, the probability that 25 randomly selected individuals have an average I.Q. less than 95 is 0.0594. 9. The standard error of a sampling distribution of means

### Probability - Variable that could be used to stratify population

1. Give a variable that could be used to stratify the population for each of the following studies. List at least four subcategories for each variable. a. A political party wants to conduct a poll prior to an election for the office of U.S. senator in Minnesota b. A soft drink company wants to take a sample of soft drink purc

### Probaility Distrubution: Simulation

2. Every time a machine breaks down at the Savannah Manufacturing Co. either 1, 2, or 3 hours is required to fix it, according to the following probability distribution: Repair Time (Hours) Probability 1 .30 2

### The Savannah Manufacturing Co. produces a product for the shipping industry that uses 5 machines.

1. The Savannah Manufacturing Co. produces a product for the shipping industry that uses 5 machines. The probability distribution of the number of machines that will break down in a week is as follows: Machine Breakdowns per Week Probability 0

### Decision Based on Maximizing Expected Value

3. The concessions manager at the Clemson vs. USC football game must decide whether to have the vendors sell sun visors or umbrellas. There is a 30% chance of rain, a 15% chance of overcast skies, and a 55% chance of sunshine, according to weather forecasts for the Columbia SC on game day. The manager estimates that the followi