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Probability Distribution

1) A test consists of 690 true or false questions. If the student guesses on each question, what is the mean number of correct answers? A) 0 B) 138 C) 345 D) 690 2) IQ test scores are normally distributed with a mean of 101 and a standard deviation of 13. An individual's IQ score is found to be 103. Find the z-score corres

Sales Goals for Telemarketer

Setting goals for your sales force is a balancing act: the goal should be high enough to be challenging but not so high that there is little chance of making it - that will just depress the sales force. In telemarketing sales, only one "completed contact" (the telemarketer gets to finish the pitch on the phone) in 20 ends up t

Suppose that WPC is only considering going directly to the national market or not (ignore the test market for right now). Which of these two alternatives has the highest expected return?

2. The WP Company (hereinafter, WPC) is trying to decide whether to market a new product. As in many new product situations, there is considerable uncertainty about whether the new product will eventually "catch on" (a technical marketing term meaning "sell a lot"). WPC believes it might be smart to introduce the product in a

Probability based on normal and binomial variable

Question 6 A manager must select 2 people from a list of 13 specialized employees to form a special group. In how many ways can the manager choose to select 2 people? [Hint: Fundamental counting principle] Question 7 57% of families say that their children have an influence on their vacation destinations. Consider a random

Binomial distribution formula

Solve for the probabilities of the following binomial distribution problems by using the binomial formula. b. If n = 6 and p = .50, what is the probability that x >= 1? c. If n = 9 and p = .85, what is the probability that x > 7? d. If n = 14 and p = .70, what is the probability that x<=3? Use Table A.2, Appendix A, to fin

Statistics Multiple Choice - Probability and Z Test

11. Find the area under the normal curve to the right of z - = -1.66 a. 0.9515 b. 0.9525 c. 0.0485 d. 0.0475 12. Find the area under the standard normal curve between z= 0 and z=3 a. 0.0010 b. 0.4987 c. 0.4641 d. 0.9987 13. Find the area under the standard normal curve between z =1 and z = 2. a. 0.5398 b. 0.


Data on the 30 largest bond funds provided one-year and five-year percentage returns for the period ending March 31,2000. Suppose we consider a one-year return in excess of 2% to be high and a five-year return in excess of 44% to be high. One-half of the finds had a one-year return in excess of 2%, 12 of the funds had a five-yea

Basic Statistics in PHStat

1) Need to create a statistical table & chart in EXCEL with corresponding verbiage that describes them - with at least 5 different visuals with verbiage. See the attached example [You may need PHStat2]. 2) Need a single word file containing the excel output and written descriptions, and the verbiage that would go with des

Orlando Census

The 2000 U.S. Census data for Orlando is available at A portion of that information is shown below: Age Range Number Percent Under 5 years 12287 6.61% 5 to 9 years 12104 6.51% 10 to 14 years 10623 5.71% 15 to 19 years 10203 5.49% 20 to 24 years 15639 8.41% 25 to 34 years 39

proportion of customers spend at least $100 on non-book item

Customers at the ASU bookstore spend varying amounts of money on "non-book" items. Historical data show that the amount spent per customer is normally distributed with a mean of $85 and a standard deviation of $30. a. What proportion of customers spend at least $100 on non-book items? b. If the proportion you found in part

Probability & Chance

An investment broker at your brokerage house tells you that he has found a mutual fund that has beaten the S&P market index in 16 of the past 25 weeks. Has he really found a winner or could this be due to chance? What is the probability that this result is due to chance? (By "due to chance," we mean that there is a 50-50 chan

Decision Tree Expansion Decision

2. Shown (attached) is a decision tree describing an expansion decision. a. Are "sales" independent of the expansion decision? Why or why not? b. Are "costs" independent of the expansion decision? Why or why not? c. Are "costs" independent of "sales?" Why or why not? d. Are revenues independent of the expans

Proportion and Percentage

The monthly spending on food of a family of three in Puerto Rico for the year 2000 is estimated in an average of $420.00/month with a standard deviation of $80.00. Assuming that the monthly spending in food is distributed normally (when presenting the processes, you need to include the corresponding graphs.): a) What proportion


1.) The probability of your doctor being late for the appointment is .4 and the probability the HMO will pay for your prescription is .7 and these events are independent of each other. a) Use the letters D and H to describe the "plain" events. D=" H=" b) Write correct probability statements for the following probabilit

Operation Management - Solver Model

Here is the scenario: You have four people sitting in jail. One has committed a terrible crime. They have made the following statements: Anita says: "Kitty did it." Kitty says: "Robin did it." Ed says: "I didn't do it." Robin says: "Kitty lied." Your favorite snitch tells you that only one person is telling the

Statistical Problems

1.) Listed below is the percent increase in sales for the MG Corporation over the last 5 years. Determine the geometric mean percent increase in sales over the period. (See attached) 2.) In 1996 a total of 14,968,000 taxpayers in the United States filed their individual tax returns electronically. By the year 2002 the numbe

A. What is the probability that a subscriber rented a car for personal or business reasons? b. What is the probability that a subscriber rented did not rent a car for either personal or business reasons?

A survey of magazine subscribers showed that 55.8% rented a car during the last 12 months for business reasons, 44% rented a car for personal reasons, and 25% rented a car for both business and personal reasons. a. What is the probability that a subscriber rented a car for personal or business reasons? b. What is the probab


The availability of venture capital provided a big boost on funds available to companies recent years. According to Venture Economics, 2,374 venture capital disbursements were made in 1999. Of these 1,334 were to companies in California, 490 were to companies in Massachusetts, 117 were to companies in New York, and 212 were to c

Experimental Outcomes Probability

Suppose that we have a sample space with 5 equally likely experimental outcomes: E1, E2,E3,E4,E5. Let A={E1, E2,E3}, B={E2, E4}, C={E3,E4,E5} a. find P(A), P(B), P(C) b. find P(A intersection B) Are A and B mutually exclusive c. Find P(CC) and P(AUC)


1. Describe exactly what information is provided by a Z-score 2. A distribution has a standard deviation of Ï?=4. Find the z-score for each of the following locations in the distribution. a. Above the mean by 4 points b. Above the mean by 12 points c. Above the mean by 2 points d. Above the mean by 8 points 3. A distr

Operational Management Problems

These problems are Waiting Line Models. (1,2,3) The problems I need work out are: Problem 14, 19, and 20. See attached file for full problem description.

Four statistics and probability questions

10. The following examples are experiments and their associated random variables. In each case identify the values the random variable can assume and state whether the random variable is discrete or continuous. a. Take a 20-question exam Number of questions answered correctly b. Observe cars arriving at a tollbooth f

6 probability and statistics questions

CH3 Problem 50 The mean income of a group of sample observations is $500; the standard deviation is $40. According to Chebyshev's theorem, at least what percent of the incomes will lie between $400 and $600? CH3 Problem 62 The Citizens Banking Company is studying the number of times the ATM located in a Loblaws Supermarket

Waiting Line Model, Poisson Distribution, Exponential Distribution

A crew of mechanics at the San Jose Transportation Department garage repair vehicles that break down at an average of ë= 7.5 vehicles per day (Poisson Distribution). The crew under the supervision of the VTA city manager can service an average of ì= 10 vehicles per day with a repair time distribution that approximates an expo

Statistical Quality Control Question

The net contents in ounces of a canned soft drink is a random variable with probability distribution 4(x - 11.75) 11.75 &#61603; x &#61603; 12.25 f(x) = 4(12.75 - x) 12.25 &#61603; x &#61603; 12.75 a. Find the probability that a can contains less than 12 oz of product. b. What are the mean net contents of each c

Sampling and Business Research

Can type of sampling (probability, non-probability sampling) also affect the results of business research? Explain your answer.

Computing the Probability of a Dice Roll

An ordinary (fair) die is a cube with the numbers 1 through 6 on the sides (represented by painted spots). Imagine that such a die is rolled twice in succession and that the face values of the two rolls are added together. This sum is recorded as the outcome of a single trial of a random experiment. Compute the probability of

Binomial random variable problem

Offering tropical bananas has been the most effective way to keep employees happy. It has been shown to be 96% effective if the right kind of bananas are chosen. If 5 unhappy employees are offered the right kind of bananas, what is the probability that 4 of them are kept happy? See attached file for full problem description

The solution to Normal approximation to the binomial

A summer resort boast that 85% of its new visitors return the next five years. Use the normal approximation to the binomial to find the probability that, of 250 new visitors this summer, at least 200 will return some time within the next five years.