Exam 4: Probability

Max Sandlin is exploring the characteristics of stock market investors.He found that sixty percent of all investors have a net worth exceeding $1,000,000; 20% of all investors use an online brokerage; and 10% of all investors a have net worth exceeding $1,000,000 and use an online brokerage.An investor is selected randomly,and E is the event "net worth exceeds $1,000,000," and O is the event "uses an online brokerage." P(O|E)= _____________.

A market research firm is investigating the appeal of three package designs.The table below gives information obtained through a sample of 200 consumers.The three package designs are labeled A,B,and C.The consumers are classified according to age and package design preference. Are "B" and "25 or older" independent and why or why not?

Belinda Bose is reviewing a newly proposed advertising campaign.Based on her 15-years' experience,she believes the campaign has a 75% chance of significantly increasing brand name recognition of the product.This is an example of assigning probabilities using the ________________ method.

Abel Alonzo,Director of Human Resources,is exploring employee absenteeism at the Plano Power Plant.Ten percent of all plant employees work in the finishing department; 20% of all plant employees are absent excessively; and 7% of all plant employees work in the finishing department and are absent excessively.A plant employee is selected randomly; F is the event "works in the finishing department;" and A is the event "is absent excessively." P(A $\cup$ F)= _____________.

A market research firms conducts studies regarding the success of new products.The company is not always perfect in predicting the success.Suppose that there is a 50% chance that any new product would be successful (and a 50% chance that it would fail).In the past,for all new products that ultimately were successful,80% were predicted to be successful (and the other 20% were inaccurately predicted to be failures).Also,for all new products that were ultimately failures,70% were predicted to be failures (and the other 30% were inaccurately predicted to be successes).What is the a priori probability that a new product would be a success?

Given that two events,A and B,are independent,if the marginal probability of A is 0.6,the conditional probability of A given B will be 0.4.

Consider the following sample space,S,and several events defined on it.S = {Albert,Betty,Abel,Jack,Patty,Meagan},and the events are: F = {Betty,Patty,Meagan},H = {Abel,Meagan},and P = {Betty,Abel}.The complement of F is ___________.

A market research firm is investigating the appeal of three package designs.The table below gives information obtained through a sample of 200 consumers.The three package designs are labeled A,B,and C.The consumers are classified according to age and package design preference. If one of these consumers is randomly selected and prefers design B,what is the probability that the person is 25 or older?

A market research firm is investigating the appeal of three package designs.The table below gives information obtained through a sample of 200 consumers.The three package designs are labeled A,B,and C.The consumers are classified according to age and package design preference. If one of these consumers is randomly selected and is under 25,what is the probability that the person prefers design A?

Suppose 5% of the population have a certain disease.A laboratory blood test gives a positive reading for 95% of people who have the disease and 10% positive reading of people who do not have the disease..What is the probability of testing positive?

An automobile dealer wishes to investigate the relation between the gender of the buyer and type of vehicle purchased.Based on the following joint probability table that was developed from the dealer's records for the previous year,P (SUV)= ___________.

Meagan Dubean manages a portfolio of 200 common stocks.Her staff classified the portfolio stocks by 'industry sector' and 'investment objective.' If a stock is selected randomly from Meagan's portfolio,P (Healthcare $\cup$ Electronics)= _______.

The list of all elementary events for an experiment is called the sample space.

In a set of 25 aluminum castings,four castings are defective (D),and the remaining twenty-one are good (G).A quality control inspector randomly selects three of the twenty-five castings without replacement,and classifies each as defective (D)or good (G).The sample space for this experiment contains ____________ elementary events.

Max Sandlin is exploring the characteristics of stock market investors.He found that sixty percent of all investors have a net worth exceeding $1,000,000; 20% of all investors use an online brokerage; and 10% of all investors a have net worth exceeding $1,000,000 and use an online brokerage.An investor is selected randomly,and E is the event "net worth exceeds $1,000,000" and O is the event "uses an online brokerage." P(O $\cup$ E)= _____________.

If the occurrence of one event does not affect the occurrence of another event,then the two events are mutually exclusive.

In a set of 12 aluminum castings,two castings are defective (D),and the remaining ten are good (G).A quality control inspector randomly selects three of the twelve castings with replacement,and classifies each as defective (D)or good (G).The sample space for this experiment contains __________ elementary events.

It is known that 20% of all students in some large university are overweight,20% exercise regularly and 2% are overweight and exercise regularly.What is the probability that a randomly selected student is either overweight or exercises regularly or both?

Suppose that 3% of all TVs made by some Company in 2012 are defective.If 2 of these TVs are randomly selected what is the probability that both are defective?

An experiment is a process that produces outcomes.