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Flip a Quarter

1. A person flips a quarter, dime, and nickel. Let x be the number of tails. Complete this probability distribution table. X 0 1 2 3 P(x) 2. For the following normal distribution problems find the indicated values. Include a sketch of the appropriate area with each answer. The area to the left of z = 1.25 The are

Statistics and probability

If there are 20 people in the room, 12 men and 8 women, what is the probability of picking two people, without replacement, getting a woman on the first and a man on the second? Explain what rule of probability applies, show it, and show the numbers that apply to the problem.

Normal distribution and probability

A portfolio manager believes that tomorrow's foreign exchange rate of German marks per US dollar will be Normally distributed with mean 2.03 and standard deviation 0.08. Using the manager's numbers: 1. what is the probability that tomorrow's rate will be above 2.08? 2. what is the probably that tomorrow's rate will be below


True/False Indicate whether the sentence or statement is true or false. Question 1 Management science involves the philosophy of approaching a problem in a subjective manner. Question 2 Once management scientist makes his or her decision and recommendation to management, then typically, his or her involvement with the

Hiring of Workers Probability

Estimation of workers to be hired during 3 month period: # to be hired Probability ___________ _________ 0 5% 1 10% 2 15% 3 20% 4 3

Probability Distribution of mean income

Mean income of a sample of workers is $32,000 for 9 months with a standard deviation of $3,000. Without making as assumption about probability distribution, what is the statistically expected proportion of workers that earn less than $26,000 or more than $38,000?

Statistics - Mutually Exclusive

GIVEN: The probability of event A happening is 40%. The probability of event B happening is 50%. The probability of both happening is 30%. QUESTION: If A and B are mutually exclusive, what would be the probability of the union of these two events?

Calculating Probability

Chicken Factory has several stores in the Hilton Head, South Carolina, area. When interviewing applicants for server positions, the owner would like to include information on the amount of tip a server can expect to earn per check (or bill). A study of 500 recent checks indicated the server earned the following tip. Amount of

Normal Distribution for Inexpensive Thermormeters

Assume the readings of inexpensive thermometers for the temperature of the freezing point of water are normally distributed, have a mean of 0 degree C, and a standard deviation of 1 degree C. Find the probability that a randomly selected thermometer will have a reading of greater than -2 degree C for the freezing point of water


According to the National Climatic Data Center, Miami, Florida experienced 138 days of measurable precipitation (rain) in 1995. By comparison, the weather station at Phoenix, Arizona reported 31 days of precipitation during the same year. Neither amount of precipitation was considered unusual for these two cities. a. A day i

Susan Williams has been the production manager of Medical Suppliers, Inc.

Susan Williams has been the production manager of Medical Suppliers, Inc., for the past 17 years. Medical Suppliers, Inc., is a producer of bandages and arm slings. During the past 5 years, the demand for No-Stick bandages has been fairly constant. On the average, sales have been about 87,000 packages of No-Stick. Susan has

Decision Tree and Probability

Problem: Bill Holiday is not sure what he should do. He can either build a quadplex (i.e., a building with four apartments), build a duplex, gather additional information, or simply do nothing. If he gathers additional information, the results could be either favorable or unfavorable, but it would cost him $3,000 to gather th

Joint Probability

A joint probability can have a value ________ one. greater than less than equal to A and C B and C

Probability of a Call

Telephone calls arrive at the rate of 48 per hour at the reservation desk for the Paris Hilton. Find the probability of receiving 3 calls in five minute period.

Hypergeometric Question

I can do the Hyper formula f(x) = r N-r x n-x divided by N n but I cant figure out all my needed numbers from the problem. Problem states 20% enrolled in training dropped out without co

Probability - Nationality

We would like to make a study of poverty between Americans and Canadians. Company x picked a total of 1,000 American and Canadians in a survey. Upon examination of the collected data, it is found that there are 643 Canadians and 357 Americans in the survey. And 403 of the Canadians are rich and 240 are poor. Of the Americans

Probability with and without replacement

Company x manufactures toy panzers. Suppose that in an assortment of 20 toy panzers, there are 5 with defective turrets. Draw with and without replacement. a. If one panzer is selected at random, what is the probability that it has defective turret? b. If two panzers are selected at random, what is the probability tha

Probability in Statistics

The sales records of a real estate agency show the following sales over the past 200 days: Number of Number Houses Sold of Days 0 60 1 80 2 40 3 16 4 4 a. How many sample points are th

Probability of lottery winnings

What is the probability you will win any money in the state lottery and the probability that you will win at least $100, if the payoff for $2.00 is 0.0200; $25.00 is 0.0100; $100 is 0.0050; $500 is 0.0010; $5000 si 0.0005 and $10,000 is 0.0001? Please show step by step in detail of how you compute the answers.

Calculate the best expected pay off (EMV).

Suppose a product needs to be marketed, but the manufacturer can make the product in three ways using any one of the three designs. There are three categories of market conditions and they occur with the probabilities given in the following table: Design Market condition I with probab

Probability, Mean

1. A manufacturer of batteries for "kids' toys" wishes to investigate the length of time a battery will last. Tests results on a sample of 10 batteries indicated a sample mean of 5.67 and a sample standard deviation of 0.57. a. Determine the mean and the standard deviation b. What is the population mean? What is the best e

Probability Machine

A machine is set to pump cleanser into a process at the rate of 7 gallons per minute. Upon inspection, it is learned that the machine actually pumps cleanser at a rate described by the uniform distribution over the interval 6.5 to 7.5 gallons per minute. Find the probability that the machine pumps less than 6.75 gallons during

Find the Probability - Sample Mean Weight

The amount of corn chips dispensed into a 10 ounce bag by the dispensing machine has been identified at possessing a normal distribution with a mean of 10.5 ounces and a standard deviation of .2 ounces. Suppose 100 bags of chips were randomly selected from this dispensing machine. Find the probability that the sample mean weig

Tree Diagram & Probability

A course in statistics is one of the most difficult at the local university. Because of this, for the past decade the university has arranged for teaching assistants to hold frequent discussion sessions as part of the course. Since the inception of the discussion sessions, 50% of the students enrolled in the course regularly att

Calculation of probability and standard deviation

The results of a calculus exam are normally distributed with a mean of 76 and a standard deviation of 6. Find the percentage of students that scored above 70. 15.9 50.0 84.1 23.1 Find the standard deviation of the given probability distribution. x P(x) 0 0.24 1 0.01 2 0.12 3 0.1

Decision Making: Decision Trees

Suppose that one of our colleagues has $2000 available to invest. Assume that all of this money must be placed in one of three investments: a particular money market fund, a stock, or gold. Each dollar your colleague invests in the money market fund earns a virtually guaranteed 12% annual return. Each dollar he invests in the st

Probability calculations for Discrete distributions

Use the binomial probability formula to determine the probability of x successes in n trials: n=12, x=5, p=0.25 0.103 0.082 0.091 0.027 The probability is 0.7 that a person shopping at a certain store will spend less than $20. For groups of size 22, find the mean number who spend