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# Probability

### Statistics: normally and binomially distributed random variables

1) A videotape store has an average weekly gross of \$1,158 with a standard deviation of \$120. Assuming this to be a normally distributed random variable, calculate the following: a. Probability the weekly gross will exceed \$1,261. b. Proportion of weeks the weekly gross is less than \$1,080. c. Probability the weekly gross is

### Statistics problem

1) A survey revealed that 21.5% of the households had no checking account, 66.9% had regular checking accounts, and 11.6% had NOW accounts. Of those households with no checking account 40% had savings accounts. Of the households with regular checking accounts 71.6% had a savings account. Of the households with NOW accounts 7

### Hamburger Probability of Incidents of People Becoming Ill

Because of a recent incident in which a number of people became ill after eating undercooked hamburger meat, intensive interest has centered around the cooking time for hamburger patties. In the past, the cooking time at a local fast food firm has been found to be uniformly distributed between 4 and 5 minutes. a) A TV report

### Finding a probability given Binomial and Poisson distributions

1.The Census Bureau reports that 55% of all 3-to-5-year-old children attended preschool programs at least a portion of the day. If 18 children are chosen at random, what is the probability that fewer than six children attend such a program? 2. Experimenters in ecology found that the average density of zooplankton in a pond w

### working with probability distributions.

702) On any given day the number of leasable square feet of office space available in a small city is a normally distributed random variable within mean of 850,000 square feet and a standard deviation of 25,000 square feet. The number of leasable square feet available in another city is normally distributed with a mean of

### Probability distribution

702) On any given day the number of leasable square feet of office space available in a small city is a normally distributed random variable witha mean of 850,000 square feet and a standard deviation of 25,000 square feet. The number of leasable square feet available in another city is normally distributed with a mean of

### Probability and standard deviation

Find the probability and the z-value for the questions attached.

### Explanation of Discrete Random Variable and Continuous Random Variable and Examples

What is a discrete random variable and how does it differ from a continuous random variable? Give examples.

### Equally-likely Outcomes Model of Probability

What is the 'Equally-likely Outcomes Model of Probability?" What is the formula for this model of probability?

### Statistics and Probability

A retail grocer has decided to market organic "health food" and will purchase a new line of products from each of two suppliers. Unknown to the grocer, the two suppliers are in financial distress. Past experience has shown that, for firms with similar credit histories, the probability that bankruptcy will be initiated one year

### List the simple events in the sample for this experiment.

Please help me with the following problem: The city of a particular community consists of five elected residents of the community, two of whom are land developers. The city mayor plans to elect two members at random from the council to study and make recommendations on land use rezoning requests. The composition of this su

### Probability of a Brother Knocking Down Their Bottle

In a game at a fraternity party, there are 10 bottles to knock down. Five fraternity brothers line up to shoot the bottles down, each a perfect shot. Each brother selects one bottle at random and shoots. Find the e-value of your distribution of the number of bottles knocked down. Each brother is a perfect shot so the probabi

### Probability for Normal Distribution

X follows a normal distribution with mean 20 and standrad deviation 4. Find b such that Prob(-b<=X-20<=b)=0.95

### Distributions

A rare disease has just broken out. Doctor Johnson is trying to help, but while treating patients he might expose himself to the disease. He takes many precautions, but he doesn't know how much he's been exposed. Let the number x represent Doctor Johnson's exposure level. He doesn't know it for sure, but he assigns a uniform

### Finding the probability that the roots of a quadratic exist.

You assign uniform distributions to a, b, and c (each between 0 and 1). What is your probability that all the roots of the following equation are real? So, if you used the quadratic formula to solve the equation and you got the square root of a negative number as a root then the roots would not be real. ax^2 + bx + c = 0

### E-Value of a Distribution: Coin Flips

Bill flips a coin that can land heads or tails, and you assign equal probabilities to each, with all flips mutually irrelevant. Bill will flip the coin until he sees a consecutive sequence of tails, tails, tails. What is the e-value of your distribution of the number of flips until this happens? For example, if Bill flips HHT

### Probability of Rolling of the Die

A person rolls a pair of six-sided dice, which are equally likely to come up any number from 1 to 6. If the person rolls a seven he gets \$0. If he rolls any other number, he can choose either to win that amount or play the game again from the start. This person believes that the best strategy is to keep rolling until he gets a "

### Probability in the given situation given x-bar and sample size.

Your troop's past cookie sales went sour last year. Parents had to bail you and your troop member out of the hole. For next year the troop wants to know from your customers the planned cookie orders are likely to be for the next year. You get x-bar = \$160,000 s = \$80,000 and n = 1000. What is the probability that the r

### Statistic - Number of ways to select an object

3) Furnish 2 offices each with a desk, chair, and file cabinet and 2 bookcases. At a local store there are 6 models of desks, 8 models of chairs 4 models of file cabinets and 10 models of bookcases. How many choices do you have if you want to select two desks, two chairs, two file cabinets and four bookcases if you don't want t

### Distributions Discrete Probability Distribution

1. Find the value of (a) in the following discrete probability distribution: X -2 0 2 P(x): a 0.35 0.25 2. A binomial distribution is based on n=25 and p=0.1. Find the probability that x =1. 3 A production process produces parts with weights that are normally distributed with a mean of 1.75 ounces and a standard devi

### Probability calculation using Normal Distribution

Mean=76, standard deviation=12; Subject Q had a score of 70. a. What proportion of the population scored below Q? b. If you changed the mean to 100 and the standard deviation to 10, what would Q's score be?

### Calculate the probability that the sample mean of a variable falls in some range.

At a computer manufacturing company, the actual size of computer chips is normally distributed with a mean of 1 centimeter and a standard deviation of 0.1 centimeter. A random sample of 12 computer chips is taken What is the probability that the sample mean will be below 0.95 centimeters?

### Working with sampling distribution and probability.

A southern state has an unemployment rate of 6%. The state conducts monthly surveys in order to track the unemployment rate. In a recent month, a random sample of 700 people showed that 35 were unemployed. a) If the true unemployment rate is 6%, describe the sampling distribution of p^. b) Find P(p^ >= 0.05) c) Assum

### Calculating the probability that a mean cost will be less than a specified number given standard deviation.

The average cost of XYZ brand running shoes is \$83 per pair, with the standard deviation of \$8.00. If 9 pairs of running shoes are selected, find the probability that the mean cost of a pair of shoes will be less than \$80. Assume the variable is normally distributed.

### Determining if the normal approximation to the binomial distribution should be used.

Determine if the normal approximation to the binomial distribution could be used for the following problems: A.) A study found that 1% of Social Security recipients are too young to vote. 800 Social Security recipients are randomly selected. B.) A study found that 30% of the people in a community use the library in one yea

### Statistics: Cloning Human Embryos

A recent Survey indicated that 18% of America adults were in favor of cloning human embryos. What is the probability that in a group of 30 adult Americans, three or four will be in favor of cloning human embryos? Show your work.

### Working with probability given a specific situation

Do you try to pad your insurance claim to cover your deductible? About 40% of all U.S. adults will try to pad their insurance claims. Suppose that you are the director of an insurance adjustment office. Your office has just received 128 insurance claims to be processed in the next few days. What is the probability that a. ha

### Working with Normal Distribution and Probability

The average hourly wage of workers in a fast food restaurant is \$5.85 with a standard deviation of \$0.35. Assume that the distribution is normal. If a worker at this fast food restaurant is selected at random, what is the probability that the worker earns more than \$6.25 an hour?

### Working with binomial probability.

A die is rolled 12 times. Find the probability of rolling the following. (a) No more than 1 one

### Probabilities

1.Find the probabilities for the standard normal random variable z: P(-1.55<z<.44) 2. Find zo such that P(-zo<z<zo)=.99 3. A normal random variable x has mean =1.20 and standard deviation =.15. Find the probability of the x value. 1.35<x<1.50 b. x>1.38 4. Assume the heights of men have a mean of 69 inches with a stan