Quiz 1 Chapter 2

• True

• False

A mutual fund company offers its customers a variety of funds, including a money-market fund, three different bond funds (short, intermediate, and long-term), two stock funds (moderate and high-risk), and a balanced fund. The percentages of customers who own shares in just one fund are as follows: Money-market 20%, High-risk stock 18%, Short bond 15%, Moderate-risk stock 25%, Intermediate Balanced 7%, bond 10%, and Long bond 5%. If a customer who owns shares in just one fund is randomly selected, what is the probability that the selected individual owns shares in the balanced fund?

• 5%

• 7%

• 10%

• 18%

Consider the type of clothes dryer (gas or electric) purchased by each of five different customers at a certain store. If the probability that at most one of these purchases an electric dryer is .428, what is the probability that at least two purchase an electric dryer?

• 0.572

• 0.428

• 0

• 1

The computers of six faculty members in a certain department are to be replaced. Two of the faculty members have selected laptop machines and the other four have chosen desktop machines. Suppose that only two of the setups can be done on a particular day, and the two computers to be set up are randomly selected from the six. What is the probability that both selected setups are for laptop computers?

• 0.133

• 0.333

• 0.067

• 0.2

As of April 2006, roughly 50 million .com web domain names were registered. How many domain names consisting of just two letters in sequence can be formed? How many domain names of length two are there if digits, as well as letters, are permitted as characters?

• 6760

• 260

• 676

• 1296

A production facility employs 10 workers on the day shift, 8 workers on the swing shift, and 6 workers on the graveyard shift. A quality control consultant is to select 5 of these workers for in-depth interviews. Suppose the selection is made in such a way that any particular group of 5 workers has the same chance of being selected as does any other group (drawing 5 slips without replacement from among 24). What is the probability that all 5 selected workers will be from the day shift?

• 0.00593

• 0.02352

• 0.00396

• 0.00423

The population of a particular country consists of three ethnic groups. Each individual belongs to one of the four major blood groups. The accompanying joint probability table gives the proportions of individuals in the various ethnic group–blood group combinations. ...

• 0.500

• 0.447

• 0.200

• 0.100

Certain shop repairs both audio and video components. ...

• 0.252

• 0.212

• 0.0337

• 0.0833

An oil exploration company currently has two active projects, one in Asia and the other in Europe. Let A be the event that the Asian project is successful and B be the event that the European project is successful. If the Asian project is not successful, what is the probability that the European project is also not successful?

• 0.3

• 0.6

• 0.4

• 0.7

A quality control inspector is examining newly produced items for faults. The inspector searches an item for faults in a series of independent fixations, each of a fixed duration. Given that a flaw is actually present, let p denote the probability that the flaw is detected during any one fixation (this model is discussed in “Human Performance in Sampling Inspection,” Human Factors, 1979: 99–105). If when a flaw has not been detected in three fixations, the item is passed, what is the probability that a flawed item will pass inspection?

• 1−p

• (1−p)^3

• (1−p)/3

• 3(1−p)