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Probability of events using a standard deck of playing cards

1. You possess a 'standard deck of playing cards' (n = 52). First, (a) identify the probability of selecting a spade, club, or heart. Second, (b) calculate the probability of selecting a spade, heart, diamond, or face card. Identify (c) the probability of selecting (in sequence) a two and a red jack (assuming that the fi

Probability computation

1. A real estate investor has two houses: A and B. Each house may increase in value, decrease in value, or remain unchanged. Consider the experiment of investing in the two houses and observing the change (if any) in value: a. How many experimental outcomes are possible? b. Show a tree diagram for the experiment.

Calculate probability of different outcomes conditional on favorable reviews

A manufacturing company is trying to decide whether to add a new product line and the marketing department has been asked to help with this decision. Information on previous products produced indicates that 10% are huge successes, 20% are modest successes, 40% break even, and 30% are losers. However before the product decision


1) The time it takes for a light bulb to burn out. Continuous The weight of a t-bone steak Continuous The number of people in class who have type B blood. Discrete 2) The mean (expected value) of the random variable is 3) The variance of the random variable is 4) The standard deviation of the ran

Decision Trees and portfolio theory

Q1 A company has developed two types of synthetic fuel. However it has not developed efficient manufacturing processes for either of them. It has has the option to develop the manufacturing process for both, either or none of them. They estimate that if they try to develop a process for fuel A then their probability of success

Statistics Questions

1.Blood cocaine concentration (mg/L) was determined both for a sample of individuals who had died from cocaine-induced excited delirium (ED) and for a sample of those who had died from a cocaine overdose without excited delirium (non-ED); survival time for people in both groups was at most 6 hours. The accompanying data comes fr

Conditional probability problems: What is the probability that a student who has failed the test came from the south district? What is the probability that a student from the entire school system, chosen at random, has passed?

1.) a metropolitan school system consists of two districts- north and south. the north district contains 60% of all students, and the south district contains 40% of all students. a minimum competency test was given to all students. 10% of the north district students failed, and 15% of the south district students failed. What


A group of n people meet at lunch for a cup of coffee. They play a game to see who gets to pay for all the coffees. Each person flips a coin. If all the coins come up the same except for one person, then that one person gets to pay for all the coffee. If the coins do not result in this way, then everyone flips again until there


CareNow keeps careful track of the number of emergency room visits and is particularly interested in tracking the number of patients during the summer months (historically the peak of the ER visits). Last summer ( a90-day period covering June-July-August), the number of patients seen is X The results are on the table below. C

Probability - Corrective Shoes and Major Dental Work

Regular physical examinations are conducted annually as part of a health service program for Phoenix, Inc., employees. It was discovered that 8 percent of the employees need corrective shoes, 15 percent need major dental work, and 3 percent need both corrective shoes and major dental work. What is the probability that an empl

Probability for a Ball Season

Bob Jones of the Alaskan Bears baseball club had the highest batting average in the 2000 Major League Baseball season. His average was .335. So assume the probability of getting a hit is .335 for each time he batted. In a particular game assume he batted three times. a. This is an example of what type of probability? b. Wh

A) What is the mean and standard deviation of the number of male members of the group? B) Use the normal approximation to find the probability that less than half of the members of the group are male. C) Use the normal approximation to find the probability that the number of male members of the group is between 45 and 55.

According to a recent census, 52.2% of New York residents are male. Suppose a group of 100 New York residents are selected at random. A) What is the mean and standard deviation of the number of male members of the group? B) Use the normal approximation to find the probability that less than half of the members of the group are


Age effects in medical care. The type of medical care a patient receives may vary with the age of the patient. A large study of women who had a breast lump investigated whether or not each woman received a mammogram and a biopsy when the lump was discovered. Here are some probabilities estimated by the study. The entries in the

General Statistics

1. The weekly salaries of teachers in one state are normally distributed with a mean of $490 and a standard deviation of $45. a. What is the probability that a randomly selected teacher earns more than $525 per week? b. What is the probability a randomly selected teacher earns less than $435 per week? 2. The i

Probability of a sample proportion

A market research firm conducts telephone surveys with a 40% historic response rate. What is the probability that in a new sample of 400 telephone numbers, at least 150 individuals will cooperate and respond to the questions? In other words, what is the probability that the sample proportion will be at least 150/400=.375

Financial advisor using Decision Tree

A financial advisor has recommended two possible mutual funds for investment: Fund A and Fund B. The return that will be achieved by each of these depends on whether the economy is good, fair, or poor. A payoff table has been constructed to illustrate this situation: Investment Good Economy Fair economy Poor Economy Fund A $10

Statistics questions

1. The table below describes the smoking habits of a group of asthma sufferers. Nonsmoker Occasional Regular Heavy Total _________ Smoker Smoker Smoker_______ Men 424 39 72 36 571 Women 360 46 77 44 527_ Total 784 85 149 80 1098 a. If one of the people is randomly selected, find the probability of getti

Probabilities, z scores and distributions

1. Two hundred raffle tickets are sold. Your friend has 5 people in her family who each bought two raffle tickets. What is the probability that someone from her family will win the raffle? 2. Answer the following: a. What does it mean to say that x = 152 has a standard score of +1.5? b. What does it mean to say that a

Probability Exclusive Events

1. The events A and B are mutually exclusive. Suppose P(A) = .30 and P(B) = .20. What is the probability of either A or B occurring? What is the probability that neither A nor B will happen? 2. A study by the National Park Service revealed that 50% of vacationers going to the Rocky Mountain region visit Yellowstone Park, 4

5 Statistics Questions

1. Assume that 12 jurors are selected from a population in which 50% of the people are Mexican-Americans. The random variable X is the number of Mexican-Americans on the jury. X 0 1 2 3 4 5 6 7 8 9 10 11 12 P(x) 0.000 0.003 0.016 0.054 0.121 0.193 0.226 0.193 0.121 0.054 0.016 0.003 0.000 a. Find the probability of exac

Simple Statistics Problems (Entry Level)

4. For a population with μ=50 and σ=10. a. Find the z-score for each of the following X values. (Note: You should be able to find these values using the definition of a z-score. You should not need to use a formula or do any serious calculations.) X = 55 X = 60 X = 75 X = 45 X = 30 X = 35 b. Find the score (X

Probability of error

A typesetter, on average, makes one error in every 500 words typeset. A typical page contains 300 words. What is the probability that there will be no more than two errors in five pages. And is it possible to use a normal distribution to solve the problem or not?

Random Samples

1. A Private firm reports that 8% of the 2 million small businesses who apply for loan each year receive special interest rate (usually higher than market rate) because of high riskiness associated with small business. Consider a random sample of 25 small businesses who have recently applied for the loan a. What is the probab

Queuing Theory - Single-Channel Waiting Line Model

Marty's Barber Shop has one barber. Customers have an arrival rate of 5 per hour. Use the Poisson arrivals and exponential service times model to answer the following questions: a). What is the probability that no units are in the system? b). What is the probability that one customer is receiving a haircut and no one is wait


The stock broker estimates that the probabilty that the price of 3 stocks will rise 0.4,0.5, and 0.7 respectively. What is the probability that the prices of all three stocks will rise (assume independence)

Powerball Winning Combinations, Prizes, and Probabilities

Case Study: The Powerball 1. Review the case study on page 157 of the textbook. See other attachments 2. Recall that for a single ticket a player first selects five numbers from the numbers 1-55 and then chooses a Powerball number, which can be any number between 1 and 42. A ticket costs $1. In the drawing five white balls are