Exam 4: Introduction to Probability

Three events occur with probabilities P(E₁)= 0.35,P(E₂)= 0.15,P(E₃)= 0.40.If the event B occurs,the probability becomes P(E₁|B)= 0.25,P(B)= 0.30.Compute P(E₁ or B).

A New Jersey company relies on a steady supply of power to keep its manufacturing going.Recently at a planning meeting,the general manager stated that the chance of a rolling blackout affecting production is 0.15.She most likely made this assessment using subjective probability assessment.

The following probability distribution was subjectively assessed for the number of sales a salesperson would make if he or she made five sales calls in one day. Given this distribution,the probability that the number of sales is 2 or 3 is 0.50.

When the salesperson makes a sale,there are three possible sales levels: large,medium,and small.The probability of a large sale is 0.20 and the chance of a medium sale is 0.60.If a salesperson makes two sales,the probability that at least one is large is 0.36.

In playing the game Monopoly,the probability of a player landing on Park Place would be assessed using classical probability assessment.

Suppose a quality manager for Dell Computers has collected the following data on the quality status of disk drives by supplier.She inspected a total of 700 disk drives. Based on these inspection data,what is the probability of randomly selecting a disk drive from company B?

The Baker Oil and Gas Company has four retail locations,code-named A,B,C,and D.The following table illustrates the percentage of total company sales at each store and also the percentage of customers at that store who make purchases with debit cards: Based on this information,the probability that a customer who used a debit card shopped at store C is 0.0738.

The URS construction company has submitted two bids,one to build a large hotel in London and the other to build a commercial office building in New York City.The company believes it has a 40% chance of winning the hotel bid and a 25% chance of winning the office building bid.The company also believes that winning the hotel bid is independent of winning the office building bid. What is the probability the company will lose both contracts?

The owners of Greg's Department Store have reason to believe that one of their employees has been stealing from the store.In an interview with the police,the owner says that she is 75 percent sure that the employee is stealing.This probability is an example of one that was assessed using classical probability.

Vegetables from the summer harvest are currently being processed at Skone and Conners Foods,Inc.The manager has found a case of cans that has not been properly sealed.There are three lines that processed cans of this type,and the manager wants to know which line is most likely to be responsible for this mistake.Provide the manager this information.

The managers of a local golf course have recently conducted a study of the types of golf balls used by golfers based on handicap.A joint frequency table for the 100 golfers covered in the survey is shown below: Based on these data,the probability of a golfer having a handicap less than 10 is:

A study was recently done in which 500 people were asked to indicate their preferences for one of three products.The following table shows the breakdown of the responses by gender of the respondents. Based on these data,the probability that a person in the population will prefer product A can be assessed as:

Mutually exclusive means that the occurrence of event A has no effect on the probability of the occurrence of event B,and independent means the occurrence of event A prevents the occurrence of event B.

Micron Technology has sales offices located in four cities: Dallas,Seattle,Boston,and Los Angeles.An analysis of the company's accounts receivables reveals the number of overdue invoices by days,as shown here. Assume the invoices are stored and managed from a central database. If a randomly selected invoice is from the Los Angeles office,what is the probability that it is 60 or fewer days overdue?

If a six-sided die is tossed two times and "4" shows up both times,the probability of "4" on the third trial is much larger than any other outcome.

Based on weather data collected in Racine,Wisconsin,on Christmas Day,the weather had the following distribution: /Thompson_sn3t_WordExports/Thompson_sn3t_WordExports Based on these data,what is the probability that next Christmas will be dry?

Drake Marketing and Promotions has randomly surveyed 200 men who watch professional sports.The men were separated according to their educational level (college degree or not)and whether they preferred the NBA or the National Football League (NFL).The results of the survey are shown: Suppose a survey participant is randomly selected and you are told that he has a college degree.What is the probability that this man prefers the NFL?

The managers of a local golf course have recently conducted a study of the types of golf balls used by golfers based on handicap.A joint frequency table for the 100 golfers covered in the survey is shown below: Based on these data,if a player has a handicap that is 10 or more,the probability that he or she will use a Nike golf ball is:

At gambling casinos all over the country,a popular dice game is called craps.The probability of a player winning at this game can be assessed using:

The Anderson Lumber Company has three sawmills that produce boards of different lengths.The following table is a joint frequency distribution based on a random sample of 1,000 boards selected from the lumber inventory. Based on these data,if a board is selected that is 12 feet long,the probability that it was made at sawmill A is: