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Normal random variable

A drug company believes that the annual demand for a drug will follow a normal random variable with a mean of 900 pounds and a standard deviation of 60 pounds. If the company produces 1000 pounds of the drug, what is the chance (rounded to the nearest hundredth) that it will run out of the drug? Assume that the only way to meet

Probability Statistics Problem

Suppose that 1% of all people have a particular disease. A test for the disease is 99% accurate. This means that a person who test positive for the disease has a 99% chance of actually having the disease, while a person who test negative for the disease has a 99% chance of not having the disease. If a person tests positive fo

A roulette wheel contains the integers 1 through 36, 0, 00

A roulette wheel contains the integers 1 through 36, 0, 00. Suppose that you spin the wheel 6 times and that each time you bet on a single number. What is the probability (rounded to nearest 100th) that you win on at least one bet? Possible answers: 0.09, 0.11, 0.13, 0.15, none of the above.

Joint Probability Table

Health Insurance (Proportion of Population) Yes No Age 18 to 34 750 170 35 and older 950 130 a. Develop a joint probability table for these data and use the table to answer the remaining questions. b. What do the mar

Probability and Life Expectancy

The following table is from the Social Security Actuarial Tables. For each age, it gives the probability of death within one year, the number of living out of an original 100,000 and the additional life expectancy for a person of that age. Determine the following using the table: a. To what age may a female of age 60 expect

Probability: Computations Based on Gender and Job Specifications

Question: The Penguin Company employs 200 men and 50 women. Of the male employees, 140 work in the plant, 20 are in the office, and 40 are field salesmen. The female employees are distributed as follows: 10 to the plant, 25 to the office, and 15 to the sales. If the CEO, Stephanie, randomly selects an employee to tour a factory

Needing extra help with homework

I am having issues resolving the following and need extra help please: 1. If the probability that it will rain tomorrow is 0.26, what is the probability that it will not rain tomorrow 2. Find the probability of getting a number greater than 4 when a die is rolled one time 3. An apartment building has the following apartments

Probability of Member Lift Weights

I am having issues resolving some of my homework and need an extra help: 1. A jar contains only red marbles and green marbles. If a marble is selected at random from the jar, the probability that a red marble will be selected is 2/3. If there are 18 green marbles in the jar, how many red marbles are there in the jar 2. Find th

Probability - CNP Bank Card Problem 1. Score each of these customers and estimate their probability of being profitable. 2. What is the probability that all three are profitable? 3. What is the probability that none of them are profitable? 4. Find the entire probability distribution for the number of profitable customers among this group of three. 5. Write a brief summary of your findings.

1. CNP Bank Card Before banks issue a credit card, they usually rate or score the customer in terms of his or her projected probability of being a profitable customer. A typical scoring table appears below. See attachment fot table The score is the sum of the points on the six items. For example, Sushi Brown is under 25 y


In a study, serum cholesterol levels were measured for a large number of healthy males. The population was then followed for 16 years. Afterwards the men were divided into two groups: those who had developed coronary heart disease and those who had not. The distributions of the initial serum cholesterol levels for each group w


Estimates for the prevalence of Alzheimer's disease provided by an observational study are listed below: Prevalence of Alzheimer's disease (cases per 100 individuals) Age-group Males Females 65-69 1.3 0.5 70-74 3.3 2.1 75-79 4.9 3.8 80-84 7.5 8.2

Statistics of Bladder Cancer and Death

Assume that the bladder cancer death rates in the USA in 2009 are estimated to be 0.48 deaths per 10,000 individuals. Using the US bladder cancer rate (above) as the standard (expected rate value), you are asked to investigate the number of deaths due to bladder cancer for 10,000 workers in a specific tire plant in 2009.


Suppose that infants are classified as low birth weight if they have birth weight 2500g, and as normal birth weight if have birth weight 2501g. Suppose that infants are also classified by length of gestation in the following four categories: <20 weeks, 20-27 weeks, 28-36 weeks, >36 weeks. Assume the probabilities of the di

Standard Normal Distribution

Question 1 Use Appendix Table for Normal Distribution to find area under Standard Normal Distribution curve to the left of z = 0.85 Answer 0.8023 0.6245 0.3524 0.0582 Question 2 Use Appendix Table for Normal Distribution to find area under

Normal Probability Honda Insight

Introduced in the 2000 model year, the Honda Insight was the first hybrid automobile sold in the United States. The mean gas mileage for the model year 2005 Insight with an automatic transmission is 56 mpg on the highway. Assume the gasoline mileage of this mileage is approximately normally distributed with a standard deviation

Probability Distribution of Gender Differences

• Begin your report to by first providing an overview of the database, such as a story about the characteristics with the types of variables included Discuss the following in your report • What is the distribution of individuals by gender? • What is the "length of sentence" distribution by gender? • What percenta


The time required to complete a project is known to be normally distributed with a mean of 44 weeks and a standard deviation of 8 weeks. a) What is the probability that the project is finished in 40 weeks or fewer? b) What is the probability that the project is finished in 52 weeks or fewer? c) There is an 95 percent cha

Calculate the standard deviation of the returns.

1. Buxton Corporation is planning to invest in a security that has several potential rates of return. Using the following probability distribution of returns during different states of the economy, what is the expected rate of return on this investment? In addition, compute the standard deviation of the returns. Finally, briefly

Probability - normal distribution

1. If a fair coin is tossed 20 times then the probability of exactly 10 Tails is more than 15 percent. 2. The fill weight of a certain brand of adult cereal is normally distributed with a mean of 910 grams and a standard deviation of 5 grams. If we select one box of cereal at random from this population, what is the probabili

Normal distribution

Very difficult subject material for me. 1. Given a normal distribution with mean=100 and variance/S.D. = 10, what is the probability that a. X>75? B. X<70? C. X<80 or X>110? D. Between what two X values (symmetrically distributed around the mean) are 80% of the values? 2. A statistical analysis of 1,000 long-distance tele

Probability Distributions- Graduate Studies Level

I encourage you to use PHStat as much as possible and attach PHStat outputs to your work. No manual calculation is required. [1] As reported by Runner's World magazine, the times of the finishers in the New York City 10-km run are normally distributed with a mean of 61 minutes and a standard deviation of 9 minutes. Let x be t


3. Historically, demand for a product has been normally distributed. You collect 12 months of demand data (shown in Demand tab). Use this data to estimate your population parameters. a. What is the probability that demand will be equal to the mean? b. What is the probability that demand will be less than the mea

Probability Concept Scenarios

Please help me to check my answers to the following questions. Please show your work so that I may follow and compare against my own: a) In how many ways can seven banquet speakers be seated along one side of the head table? b) Gym lockers are to be numbered from 1 to 99 using individual metal number plates to be

Test slow paying accounts for a local wholesaler

The slow paying accounts for a local wholesaler are normally distributed with a mean of 20 accounts and a standard deviation of 4 accounts. What is the probability of randomly selecting an account and finding that it is slow? What is the probability of selecting an accounting period that has more than 25 slow paying accounts

Statistics: Within what range would 85% of credit score fall

The credit score of a 35 applying for a mortgage is normally distributed with a mean score of 600 and a standard deviation of 100. What credit score defines the top five percent of scores. Within what range would 85% of credit score fall. One hundred car tires are tested and the mean useful life comes out to 50,000 and the

Probability of Correctly Selecting Winning Lottery Numbers

A certain state is contemplating creating a weekly lottery, the revenues from which will be used to fund improvements in the state's public education system. The commission chartered to develop the guidelines for the proposed lottery envisions using a process whereby six (6) balls will be randomly selected from a single bin cont

Statistics: Five Probability multiple choice questions

1. A kindergarden class consists of 14 boys and 11 girls. If the teacher selects children from the class using random sampling: a. what is the probability that the first child selected will be a girl? b. if the teacher selects a random sample of n=3 children and the first two children are both boys, what is the probability

Probability: Reading speed of second grade students in large city

The reading speed of second grade students in a large city is approximately normal, with a mean of 91 wpm and standard deviation of 10 wpm. (a) What is the probability a randomly selected student in the city will read more than 95 wpm? (b) What is the probability that a random sample of 11 second grade students from the ci

Finding Probability and Confidence Intervals

Of the members of a Boy Scout troop, 15% have received the first aid merit badge. If 40 boy scouts are selected at random, find the probability that four or more will have the first aid merit badge? A) 86.6% B) 81.3% C) 36.6% D) 31.3% A food snack manufacturer samples 9 bags of pretzels off the assembly line and weig