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Probability of patient surviving from disease

1. The probability that a patient recovers from a disease is 63%. What is the probability that: A) 2 out of 3 patients in a group with the disease will survive? B) Probability that all 3 will survive? Answers: Just show me how to get there. A) 44.1% B) 25% 2. There are 3 consulting firms that have the following

Example Statistics Problems

1. A study of a court system produced the following results: Note: G= guilty , G' = not guilty , J= judged guilty , J'= judged not guilty 80% of guilty (G) judged guilty (J) 93% of innocent (G') judged innocent (J') 5% innocent (G') judged guilty (J) 77% guilty (G) A) Find probability judged guilty (means find P(J

Find the standard deviation of the distribution

A marketing poll revealed that 45% of Americans say they that they have dinner regularly as a family. You randomly choose 10 American families and ask if they regularly have dinner together as a family. 1. Does this situation meet the binomial requirements? Why or why not? Address the four characteristics in the Key Points.

Probability of Sample Proportion

Cashier records from the last year show that 60% of all Grayson's Grocery store customers use a previously-obtained Grayson's discount card upon checkout. Management suspects the percentage of actual cardholders is higher because some customers may not use their Grayson's card during every visit They decide to sample random cust

Sampling Distributions of diameter widths of steel rebar

The population of diameter widths of steel rebar is normally distributed with a mean of 2.5cm and a standard deviation of 0.25cm. What is the probability that the average diameter width of a strip of rebar from a sample of 23 strips is more than 2.6cm wide?

Census: Joint Probability Distribution Table

Please help with this problem: Using the data in the Excel file Census Education Data, construct a joint probability distribution for marital status and educational status. a. What is the probability that a person is divorced and has a bachelor's degree? b. What is the probability that someone known to have an advanced

Calculate the Probability for a Silver Dollar Flipped Twice

A silver dollar is flipped twice. Calculate the probability of each of the following occurring: a. a head on the first flip b. a tail on the second flip given that the first toss was a head c. two tails d. a tail on the first and a head on the second e. a tail on the first and a head on the second or a head on the first a

Binomial Random Variable Application

Rob works in quality at a well known saw blade company. An inspector on his team has uncovered an issue with the kerf dimension on the bandsaw blade line. Rob conducts a sampling study and finds that 7% of the bandsaw blades are out of spec. Unfortunately, a shipment of 25 bandsaw blades left the plant about 3 hours before t

Borrower Characteristics

1. In examining borrower characteristics versus loan delinquency, a bank has collected the following information. 15% of borrowers who have been employed at their present job for less than 3 years are behind in their payments, 5% of the borrowers who have been employed at their present job for at least 3 years are behind in the

Probability: Random Variable, Mean, Variance & Density Function

Please see the attached file for properly formatted problem descriptions. (1) The random variable X takes on the values 0, 1,2,3 with respective probabilities 1 12 48 64 125' 125' 125' 125 (a) Find E(X),E(X2) and var (X) (b) Find E((3X ± 2)2 (hint: easy if you use the results in (a)) (2) A contractor's profit on a co

Nash Equilibria

The 31 members of the board of the Student S Inc. are about to take a secret ballot whether to accept the merger proposal of Student G. Corp. Each member can vote to accept the proposal, reject the proposal or to abstain. For the proposal to be accepted, 16 members must vote to accept it. All, the 31 members care about is being

Binomial, Poisson, Normal Distribution; Confidence Intervals

See attached file. Binomial Distribution Determine whether or not the given procedure results in a binomial distribution. 1. Twenty different students are randomly selected from those attending a private boys school and asked whether he or she is traveling over the Christmas holidays. 2. A six-sided die is rolled

Gender of Children, Birth Dates, Kentucky Lottery

See attached file. You may use a calculator on this assignment. Please show work where applicable as this will help me when assigning partial credit. Probability Questions 1. Find the probability of a couple having at least 1 girl among 7 children. Assume that boys and girls are equally likely and that the gender of a

Statistics: Mike's Ice Cream mean sales; math aptitute test for college freshman

Part 2. Evaluate probabilities using the laws of probability, the standard normal distribution, t-distribution, or X2-distribution. Mike's Ice Cream shop sells ice cream and related products. Past experience indicates that the daily sales follow a probability distribution that has a mean of $1000 and a standard deviation of $

Selected employee has a technical job or is a soccer fan

See attached file. In a large corporation a sample of 136 employees have been classified according to the type of work and asked their preferred sport. The results are presented in the accompanying table. assume that one employee in this sample is selected at random. Find the indicated probabilities (express them as a decimal

Conditional probability: LAN shutdown

The local area network (LAN) for the faculty of engineering computing system at the University of Waterloo is temporary shut down for repairs. Previous shut downs have been due to hardware failure, software failure or power failure. Maintenance engineers have determined that the probabilities of hardware, software and power prob

Sampling in statistics and acceptance regions

Q1 - The probability of accepting a lot that is 10% defective is .677. Does that mean, then, that the probability of rejecting the lot is 0.333? Q2 - An acceptance sampling plan states that twenty 2-inch squares of the incoming material must be checked and if 3 or less squares are imperfect, the lot is accepted. What is the

A tire company has developed a new type of tire: Probability analysis of miles

A Tire company has developed a new type of tire. Extensive testing shows that the number of miles the new tire will run before wearing out is normally distrubuted with a mean of 40,000 miles and a standard deviation of 4,000 miles (Hint: Sketch bell shaped curves for the three questions below. a) What is the probability that

Azure Valley Electric average outage cost; TRP is offering ski chalet condos

1. Azure Valley Electric Co-operative has for many years contracted with a neighboring utility to handle emergency service requests which occur, primarily due to storm damage, at the average rate of 2 per hour. It now feels that it should probably assume this responsibility itself and has been presented with two proposals for v

Statistics: Probability value, Probability distribution

See attached file for formulas. 2. Based on FAA estimates the average age of the fleets of the ten largest U.S. commercial passenger carriers is 13.4 years with a standard deviation of 1.7 years. Suppose that 40 airplanes were randomly selected from the fleets of these ten carriers and were inspected for cracks in the airplan

Determining EMV & EOL for vendor at baseball stadium

Q3. Determining EMV & EOL A vendor at the a baseball stadium must decide whether to sell ice cream or soft drinks at today's game. The vendor believes that that the profit will depend on the weather. On the basis of her past experience at this time of year, the vendor estimates the probability of warm weather as 0.60 and cool

Probability distribution that you will receive a sample mean grand prize

Game show shows you a large revolving drum containing four identical white envelopes that have been thoroughly mixed in the drum. Each of the envelopes contains one of four decks made out for grand prizes of 20, 40, 60, and 80 thousand dollars. Usually, a contestant reaches into the drum, selects and envelope, and receives the g

How to Calculate Probability for Sale of Wind Insurance

A company examines homeowners records and sees that the mean loss from wind annually is $250 per house with std dev of $1000. They plan to sell wind insurance for $250 + estimates coverage costs & profits. i) If they sell 10,000 policies, what is the probability that annual average loss is greater than $275? ii) What shape

Binomial & Normal Probabilities Interpretations

Please provide step by step solution. Instructions: Solve the following problems keep the guidelines below in check. If you are calculating something using a table, the number of decimal places from the table is expected. like z=1.00, table value is .8413 (2 decimal places for z, 4 for the probability) REGARDING NUMBER

Lottery profits, Probability Distribution, Mary's grades this semester

Please provide step by step solution. Instructions: Solve the following problems keep the guidelines below in check. If you are calculating something using a table, the number of decimal places from the table is expected. like z=1.00, table value is .8413 (2 decimal places for z, 4 for the probability) REGARDING NUMBER

variance and the standard deviation of the number of admissions

The director of admissions at Kinzua University in Nova Scotia estimated the distribution of student admissions for the fall semester on the basis of past experience. Admissions Probability 1,070 0.3 1,300 0.1 1,580 0.6 -------------------------------------------------------------------------------- (1) Wha

Decision Analysis

1. The electric company is in the process of building a new power plant. There is some uncertainty regarding the size of the plant to be built. If the community that the plant will service attracts a large number of industries, the demand for electricity will be high. If commercial establishments ( offices and retail stores) ar

Probability distribution of calls received by an office on Monday

1. The number of calls received by an office on Monday morning between 8:00 AM and 9:00 AM has a probability distribution with a mean of 4. a. What type of probability distribution is appropriate for this problem? b. Determine the probability of getting no calls between eight and nine in the morning. . c. Calculate the pro

Probability and Decision Analysis

1. Use the normal approximation without the correction factor to find the probabilities in the following exercises. a. In a binomial experiment with n = 300 and p=.5, find the probability that P is greater than 60%. b. Repeat Part a with p = 55 c. Repeat Part a with p = .6 2. Determine the probability that in a sample