The Equal Employment Opportunity Act requires employers to classify their employees

by gender and national origin. Which level of measurement is this?

The names of the positions in a corporation, such as chief operating officer or controller,

are examples of what type of variable?

When TV advertisements report "2 out of 3 dentists surveyed indicated they would

recommend Brand X toothpaste to their patients," an informed consumer may question

the conclusion because the:

Which of the following is an example of a continuous variable?

What type of variable is the number of gallons of gasoline pumped by a filling station

during a day?

What is the median of 26, 30, 24, 32, 32, 31, 27, and 29?

A bottling company offers three kinds of delivery service: instant, same day, and within

five days. The profit per delivery varies according to the kind of delivery. The profit for

an instant delivery is less than the other kinds because the driver has to go directly to a

grocery store with a small load and return to the bottling plant. To find out what effect

each type of delivery has on the profit picture, the company summarized the data in the

following table based on deliveries for the previous quarter.

What is the weighted mean profit per delivery?

A sample of small bottles and their contents has the following weights (in grams): 4, 2, 5,

4, 5, 2, and 6. What is the sample variance of bottle weight?

Refer to the following breakdown of responses to a survey of "How confident are you that

you saved enough to retire?"

What percent of the responses indicated that users were very confident?

Refer to the following distribution of ages:

What is the class midpoint of the highest class?

The monthly salaries of a sample of 100 employees were rounded to the nearest $10.

They ranged from a low of $1,040 to a high of $1,720. If we want to condense the data

into seven classes, what is the most convenient class interval?

What is the relationship among the mean, median, and mode in a symmetric distribution?

A population consists of all the weights of all defensive tackles on a university's football

team. They are Johnson, 204 pounds; Patrick, 215 pounds; Junior, 207 pounds; Kendron,

212 pounds; Nicko, 214 pounds; and Cochran, 208 pounds. What is the population

standard deviation (in pounds)?

The National Center for Health Statistics reported that of every 883 deaths in recent

years, 24 resulted from an automobile accident, 182 from cancer, and 333 from heart

disease. What is the probability that a particular death is due to an automobile accident?

If two events A and B are mutually exclusive, what does the special rule of addition

state?

A firm offers routine physical examinations as part of a health service program for its

employees. The exams showed that 8% of the employees needed corrective shoes, 15%

needed major dental work, and 3% needed both corrective shoes and major dental work.

What is the probability that an employee selected at random will need either corrective

shoes or major dental work?

A business venture can result in the following outcomes (with their corresponding chance

of occurring in parenthesis): Highly Successful (10%), Successful (25%), Breakeven

(30%), Disappointing (15%), and Highly Disappointing (?). If these are the only

outcomes possible for the business venture, what is the chance that the business venture

will be considered Highly Disappointing?

The first card selected from a standard 52-card deck was a king. If it is returned to the

deck, what is the probability that a king will be drawn on the second selection?

A study of interior designers' opinions with respect to the most desirable primary color

for executive offices showed that:

What is the probability that a designer does not prefer yellow?

The average score of 100 students taking a statistics final was 70, with a standard

deviation of 7. Assuming a normal distribution, what test score separates the top 5% of

the students from the lower 95% of the students?

The weekly mean income of a group of executives is $1,000 and the standard deviation of

this group is $100. The distribution is normal. What percent of the executives have an

income of $925 or less?

An accelerated life test on a large number of type-D alkaline batteries revealed that the

mean life for a particular use before they failed is 19.0 hours. The distribution of the lives

approximated a normal distribution. The standard deviation of the distribution was 1.2

hours. About 95.44% of the batteries failed between what two values?

For a normal distribution, what is the likelihood (expressed as a percentage) that a

random variable is within plus and minus two standard deviations of the mean?

The mean amount spent by a family of four on food is $500 per month with a standard

deviation of $75. Assuming that the food costs are normally distributed, what is the

probability that a family spends less than $410 per month?

Which of the following is true regarding the normal distribution?

Two normal distributions are compared. One has a mean of 10 and a standard deviation of

10. The second normal distribution has a mean of 10 and a standard deviation of 2. Which

of the following is true?

What is the area under the normal curve between z = 0.0 and z = 1.79?

What is the area under the normal curve between z = -1.0 and z = -2.0?

The mean score of a college entrance test is 500; the standard deviation is 75. The scores

are normally distributed. What percent of the students scored below 320?

For a normal distribution, what is the likelihood (expressed as a percentage) that a

random variable is within plus and minus two standard deviations of the mean?

The weekly incomes of a large group of executives are normally distributed with a mean

of $2,000 and a standard deviation of $100. What is the z-score for an income of $2,100?

A study of a company's practice regarding the payment of invoices revealed that an

invoice was paid an average of 20 days after it was received. The standard deviation

equaled five days. Assuming that the distribution is normal, what percent of the invoices

were paid within 15 days of receipt?

The weight of cans of fruit is normally distributed with a mean of 1,000 grams and a

standard deviation of 50 grams. What percent of the cans weigh 860 grams or less?

Suppose a tire manufacturer wants to set a mileage guarantee on its new XB 70 tire. Tests

revealed that the tire's mileage is normally distributed with a mean of 47,900 miles and a

standard deviation of 2,050 miles. The manufacturer wants to set the guaranteed mileage

so that no more than 5% of the tires will have to be replaced. What guaranteed mileage

should the manufacturer announce?

The tread life of tires mounted on light-duty trucks follows the normal probability

distribution with a mean of 60,000 miles and a standard deviation of 4,000 miles.

Suppose you bought a set of four tires, what is the likelihood the mean tire life of these

four tires is between 57,000 and 63,000 miles?

For a distribution of sample means constructed by sampling 5 items from a population of

15, ___________.

Manufacturers were subdivided into groups by volume of sales. Those with more than

$100 million in sales were classified as large; those from $50 to $100 million as medium

size; and those between $25 and $50 million, and so on. Samples were then selected from

each of these groups. What is this type of sampling called?

The wildlife department has been feeding a special food to rainbow trout fingerlings in a

pond. Based on a large number of observations, the distribution of trout weights is

normally distributed with a mean of 402.7 grams and a standard deviation 8.8 grams.

What is the probability that the mean weight for a sample of 40 trout exceeds 405.5

grams?

The size of the sampling error is ________.

All possible samples of size n are selected from a population and the mean of each sample

is determined. What is the mean of the sample means?

What is the difference between a sample mean and the population mean called?

An experiment involves selecting a random sample of 256 middle managers for study.

One item of interest is their annual income. The sample mean is computed to be $35,420,

and the sample standard deviation is $2,050. What is the sample standard error of the

mean?

According to the central limit theorem, _______________.

According to the central limit theorem, ____________.

For the following distribution:

What is the variance of the distribution?

A statistics professor receives an average of five e-mail messages per day from students.

Assume the number of messages approximates a Poisson distribution. What is the

probability that on a randomly selected day she will have no messages?

A coin is tossed four times. The following table summarizes the experiment. What is the

following table called?

A machine shop has 100 drill presses and other machines in constant use. The probability

that a machine will become inoperative during a given day is 0.002. During some days,

no machines are inoperative, but during some days, one, two, three, or more are broken

down. What is the probability that fewer than two machines will be inoperative during a

particular day?

The production department has installed a new spray machine to paint automobile doors.

As is common with most spray guns, unsightly blemishes often appear because of

improper mixture or other problems. A worker counted the number of blemishes on each

door. Most doors had no blemishes; a few had one; a very few had two; and so on. The

average number was 0.5 per door. The distribution of blemishes followed the Poisson

distribution. Out of 10,000 doors painted, about how many would have no blemishes?

A new car was put into production. It involved many assembly tasks. Each car was

inspected at the end of the assembly line and the number of defects per unit was recorded.

For the first 100 cars produced, there were 40 defective cars. Some of the cars had no

defects, a few had one defect, and so on. The distribution of defects followed a Poisson

distribution. Based on the first 100 cars produced, about how many out of every 1,000

cars assembled should have one or more defects?

A total of 60% of the customers of a fast food chain order a hamburger, French fries, and

a drink. If a random sample of 15 cash register receipts is selected, what is the probability

that 10 or more will show that the above three food items were ordered?

Judging from recent experience, 5% of the computer keyboards produced by an

automatic, high-speed machine are defective. If six keyboards are randomly selected,

what is the probability that none of the keyboards are defective?

On a very hot summer day, 5% of the production employees at Midland States Steel are

absent from work. The production employees are randomly selected for a special in-depth

study on absenteeism. What is the probability of randomly selecting 10 production

employees on a hot summer day and finding that none of them are absent?

Which one of the following is NOT a condition of the binomial distribution?

A population in statistics means a collection of all

Indicate which of the following is an example of a sample with

replacement

Indicate which of the following variables are quantitative and

continuous.

The following table gives the frequency distribution of times (to

the nearest hour) that 90 fans spent waiting in line to buy tickets to a

rock concert.

The relative frequency of the second class is

Which of the following can have more than one value?

An ice cream parlor has six flavors of ice cream. Kristen wants to buy two flavors of ice cream.

If she randomly selects two flavors out of six, how many combinations are possible?

Three members of a UPH Student committee will be randomly selected from five people. How many different

combinations are possible?

A club has 20 members. They are to select three office holders—president, secretary, and treasurer—

for next year. They always select these office holders by drawing 3 names randomly from the names

of all members. The first person selected becomes the president, the second is the secretary, and the

third one takes over as treasurer. Thus, the order in which 3 names are selected from the 20 names is

important. Find the total number of arrangements of 3 names from these 20.

Two mutually exclusive events

Two independent events

Baier’s Electronics manufactures computer parts that are supplied to many computer companies.

Despite the fact that two quality control inspectors at Baier’s Electronics check every part for

defects before it is shipped to another company, a few defective parts do pass through these

inspections undetected. Let x denote the number of defective computer parts in a shipment of

400. The following table gives the probability distribution of x.

Compute the standard deviation of x.

Seventy five percent of students at a college with a large student population use Instagram.

A sample of five students from this college is selected, and these students are

asked whether or not they use Instagram. Is this experiment a binomial experiment?

In a group of 12 students at a college, 9 use Instagram. Five students are selected from

this group of 12 and are asked whether or not they use Instagram. Is this experiment a

binomial experiment?

CLUE : BINOMIAL PROBABILITY (FOR THE SHORTCUT ANSWER YOU CAN USE TABLE)

Seventy five percent of students at a college with a large student population use the social media

site Instagram. Three students are randomly selected from this college. What is the probability

that exactly two of these three students use Instagram?

HINT : BINOMIAL PROBABILITY (FOR THE SHORTCUT ANSWER YOU CAN USE TABLE)

At the Express House Delivery Service, providing high-quality service to customers is the top

priority of the management. The company guarantees a refund of all charges if a package it is

delivering does not arrive at its destination by the specified time. It is known from past data that

despite all efforts, 2% of the packages mailed through this company do not arrive at their destinations

within the specified time. Suppose a corporation mails 10 packages through Express House

Delivery Service on a certain day.

Find the probability that exactly one of these 10 packages will not arrive at its destination

within the specified time.

CLUE : Mean and Standard Deviation of the Binomial Distribution

According to a Pew Research Center survey released on May 12, 2015, 22.8% of U.S. adults do

not have a religious affiliation (Time, May 25, 2015). Assume that this result is true for the current

population of U.S. adults. A sample of 50 U.S. adults is randomly selected. Let x be the number

of adults in this sample who do not have a religious affiliation. Find the mean and standard

deviation of the probability distribution of x.

CLUE : USER Mean and Standard Deviation Binomial Formula

According to a FindLaw.com survey of American adults women, 61% support red light

cameras at intersections (USA TODAY, January 7, 2015). Assume that this percentage is true for

the current population of adult American women. What is the probability that 500 or more such

women in a random sample of 800 women will support red light cameras at intersections?