OIS 2340 Ch 4
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. Assume that E1, E2, and E3 are independent events. Calculate P(E1 and E2 and E3). 0.475 0.575 0.075 0.021
0.021
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. Days Overdue Dallas Seattle Boston Los Angeles Under 30 days 137 122 198 287 30-60 days 85 46 76 109 61-90 days 33 27 55 48 Over 90 days 18 32 45 66 Assume the invoices are stored and managed from a central database. What is the probability that a randomly selected invoice from the database is over 90 days old and from the Seattle office? 0.0231 0.2702 0.7765 0.3461
0.0231
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 1000 boards selected from the lumber inventory. Based on these data, if three boards are selected at random, the probability that all three were made at sawmill A is: 0.334 1.00 0.556 0.037
0.037
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. Calculate P(E1 and B). 0.021 0.075 0.575 0.475
0.075
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, the probability of selecting a board from inventory that is 10 feet long is: 0.450 0.084 0.196 0.170
0.170
An inventory of appliances contains four white washers and one black washer. If a customer selects one at random, what is the probability that the black washer will be selected? 0.8 0.4 0.5 0.2
0.2
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: Sports Preference College Degree No College Degree NBA 40 55 NFL 10 95 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? 0.2000 0.6050 0.5880 0.5250
0.2000
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: Sports Preference College Degree No College Degree NBA 40 55 NFL 10 95 What is the probability that a randomly selected survey participant has a college degree and prefers the NBA? 0.2000 0.6050 0.5880 0.5250
0.2000
Cross County Bicycles makes two mountain bike models that each come in three colors. The following table shows the production volumes for last week: What is the joint probability that a product manufactured is a YZ-99 and brown? 0.1324 0.3157 0.2088 0.3819
0.2088
A distributor of outdoor yard lights has four suppliers. This past season she purchased 40% of the lights from Franklin Lighting, 30% from Wilson & Sons, 20% from Evergreen Supply, and the rest from A. L. Scott. In prior years, 3% of Franklin's lights were defective, 6% of the Wilson lights were defective, 2% of Evergreen's were defective, and 8% of the Scott lights were defective. When the lights arrive at the distributor, she puts them in inventory without identifying the supplier. Suppose that a defective light string has been pulled from inventory; what is the probability that it was supplied by Franklin Lighting? 0.33 0.18 0.29 0.45
0.29
Cross County Bicycles makes two mountain bike models that each come in three colors. The following table shows the production volumes for last week: Based on the relative frequency assessment method, what is the probability that a manufactured item is brown? 0.1324 0.2088 0.3819 0.3157
0.3157
Men have a reputation for not wanting to ask for directions. A Harris study conducted for Lincoln Mercury indicated that 42% of men and 61% of women would stop and ask for directions. The U.S. Census Bureau's 2012 population estimate was that for individuals 18 or over, 48.2% were men and 51.8% were women. This exercise addresses this age group. A randomly chosen driver gets lost on a road trip. Determine the probability that the driver is a woman and stops to ask for directions. 0.390 0.316 0.518 0.420
0.316
Students who live on campus and purchase a meal plan are randomly assigned to one of three dining halls: the Commons, Northeast, and Frazier. What is the probability that the next student to purchase a meal plan will be assigned to the Commons? 0.33 0.5 0.66 0.25
0.33
Cross County Bicycles makes two mountain bike models that each come in three colors. The following table shows the production volumes for last week: What is the probability that the product manufactured is a YZ-99? 0.1324 0.3819 0.3157 0.2088
0.3819
Men have a reputation for not wanting to ask for directions. A Harris study conducted for Lincoln Mercury indicated that 42% of men and 61% of women would stop and ask for directions. The U.S. Census Bureau's 2012 population estimate was that for individuals 18 or over, 48.2% were men and 51.8% were women. This exercise addresses this age group. Given that a driver stops to ask for directions, determine the probability that the driver was a man. 0.420 0.316 0.390 0.518
0.390
The Jack In The Box franchise in Bangor, Maine, has determined that the chance a customer will order a soft drink is 0.90. The probability that a customer will order a hamburger is 0.60. The probability that a customer will order french fries is 0.50. If a customer places an order, what is the probability that the order will include a soft drink and no fries if these two events are independent? 0.45 0.70 0.65 0.50
0.45
The Jack In The Box franchise in Bangor, Maine, has determined that the chance a customer will order a soft drink is 0.90. The probability that a customer will order a hamburger is 0.60. The probability that a customer will order french fries is 0.50. The restaurant has also determined that if a customer orders a hamburger, the probability the customer will also order fries is 0.80. Determine the probability that the order will include a hamburger and fries. 0.58 0.48 0.45 0.68
0.48
Of the last 100 customers entering a computer shop, 25 have purchased a computer. If the classical probability assessment for computing probability is used, the probability that the next customer will purchase a computer is: 0.75 0.25 0.50 1.00
0.50
Men have a reputation for not wanting to ask for directions. A Harris study conducted for Lincoln Mercury indicated that 42% of men and 61% of women would stop and ask for directions. The U.S. Census Bureau's 2012 population estimate was that for individuals 18 or over, 48.2% were men and 51.8% were women. This exercise addresses this age group. Calculate the probability that the driver stops to ask for directions. 0.316 0.518 0.390 0.420
0.518
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: Sports Preference College Degree No College Degree NBA 40 55 NFL 10 95 What is the probability that a randomly selected survey participant prefers the NFL? 0.5880 0.2000 0.6050 0.5250
0.5250
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). 0.575 0.021 0.075 0.475
0.575
Based on weather data collected in Racine, Wisconsin, on Christmas Day, the weather had the following distribution: Event Relative Frequency Clear & dry 0.20 Cloudy & dry 0.30 Rain 0.40 Snow 0.10 Supposing next Christmas is dry, determine the probability that it will also be cloudy. 0.60 0.45 0.70 0.50
0.60
Based on weather data collected in Racine, Wisconsin, on Christmas Day, the weather had the following distribution: Event Relative Frequency Clear & dry 0.20 Cloudy & dry 0.30 Rain 0.40 Snow 0.10 Based on the data, what is the probability that next Christmas will be rainy or cloudy and dry? 0.60 0.70 0.50 0.45
0.70
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. Days Overdue Dallas Seattle Boston Los Angeles Under 30 days 137 122 198 287 30-60 days 85 46 76 109 61-90 days 33 27 55 48 Over 90 days 18 32 45 66 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? 0.2702 0.7765 0.0231 0.3461
0.7765
Ponderosa Paint and Glass carries three brands of paint. A customer wants to buy another gallon of paint to match paint she purchased at the store previously. She can't recall the brand name and does not wish to return home to find the old can of paint. So she selects two of the three brands of paint at random and buys them. Her husband also goes to the paint store and fails to remember what brand to buy. So he also purchases two of the three brands of paint at random. Determine the probability that both the woman and her husband fail to get the correct brand of paint. (Hint: Are the husband's selections independent of his wife's selections?) 3/4 2/3 3/2 1/9
1/9
Ponderosa Paint and Glass carries three brands of paint. A customer wants to buy another gallon of paint to match paint she purchased at the store previously. She can't recall the brand name and does not wish to return home to find the old can of paint. So she selects two of the three brands of paint at random and buys them. What is the probability that she matched the paint brand? 3/4 1/9 2/3 3/2
2/3
A special roulette wheel, which has an equal number of red and black spots, has come up red four times in a row. Assuming that the roulette wheel is fair, what concept allows a player to know that the probability the next spin of the wheel will come up black is 0.5? Concept of mutually inclusive events Concept of dependent events Concept of mutually exclusive events Concept of independent events
Concept of independent events
In a survey, respondents were asked to indicate their favorite brand of cereal (Post or Kellogg's). They were allowed only one choice. What is the probability concept that implies it is not possible for a single respondent to state both Post and Kellogg's to be the favorite cereal? Concept of mutually exclusive events Concept of independent events Concept of dependent events Concept of mutually inclusive events
Concept of mutually exclusive events
What method of probability assessment would most likely be used to assess the probability that a customer will return a purchase for a refund? Independent probability based on two unrelated outcomes Classical probability based on the ratio of the number of ways the event can occur Relative frequency based on previous history Subjective probability based on expert opinion
Relative frequency based on previous history
Long-time friends, Pat and Tom, agree on many things, but not the outcome of the American League pennant race and the World Series. Pat is originally from Boston, and Tom is from New York. They have a steak dinner bet on next year's race, with Pat betting on the Red Sox and Tom on the Yankees. Both are convinced they will win. What probability assessment technique is being used by the two friends? Independent probability Subjective probability Relative frequency probability Classical probability
Subjective probability
Parts and Materials for the skis made by the Downhill Adventures Company are supplied by two suppliers. Supplier A's materials make up 30% of what is used, with supplier B providing the rest. Past records indicate that 15% of supplier A's materials are defective and 10% of B's are defective. Since it is impossible to tell which supplier the materials came from once they are in inventory, the manager wants to know which supplier most likely supplied the defective materials the foreman has brought to his attention. Provide the manager this information. Supplier A Supplier B Both are equally likely Cannot be determined from this information
Supplier B
The method of probability assessment that is least likely to be used by business decision makers is: subjective assessment. classical assessment. relative frequency of occurrence. None of the above is used by decision makers.
classical assessment.
When a customer enters a store there are three outcomes that can occur: buy nothing, buy a small amount, or buy a large amount. In this situation, if a customer buys a large amount, he or she cannot also buy a small amount or buy nothing. Thus the events are: mutually exclusive. all inclusive. dependent events. independent.
mutually exclusive.
The method of probability assessment that relies on an examination of historical data from similar situations is: relative frequency of occurrence. subjective assessment. historical assessment. classical assessment.
relative frequency of occurrence.
Harrison Water Sports has three retail outlets: Seattle, Portland, and Phoenix. The Seattle store does 50 percent of the total sales in a year, while the Portland store does 35 percent of the total sales. Further analysis indicates that of the sales in Seattle, 20 percent are in boat accessories. The percentage of boat accessories at the Portland store is 30 and the percentage at the Phoenix store is 25. If a sales dollar is recorded as a boat accessory, the probability that the sale was made at the Portland store is: None of the above 0.35 slightly greater than 0.43 0.2425
slightly greater than 0.43