BUS 271 - Unite One Practice Test

A large accounting firm hired seven student interns, and their hourly wages were as follows: $25, $20, $19, $18, $13, $14, and $15. Calculate the first quartile

$14.00

Five student interns report that their hourly wages are as follows: $18, $21, $16, $13, and $16. What is the median hourly salary?

$16

The numbers of hours worked (per week) by 500 statistics students are shown below. Number of hours Frequency 0-9 40 10-19 110 20-29 250 30-39 100 What is the relative frequency of students working 0-9 hours per week?

0.08

A sample of fifteen seven-year-old boys shows their favorite superheroes. Spiderman Captain America Aquaman Batman Spiderman Spiderman Iron Man Superman Spiderman Aquaman Captain America Iron Man Iron Man Batman Spiderman

0.2

The standard deviation of a sample of 49 observations equals 36. Find the variance of the sample.

1,296

An accounting firm received nine applicants for a position. The number of years of experience listed by the applicants is as follows: 9, 14, 16, 22, 9, 6, 6, 4, and 1. Calculate the interquartile range for the number of years of experience.

10

You scored in the 98th percentile on your college placement exam. Which answer is most correct?

2% scored the same or better than you on the college placement exam.

The variance of a sample of 169 observations equals 676. Find the standard deviation of the sample.

26

There are five employees in a department with the following ages: 51, 37, 27, 26, and 31. Which age represents the 40th percentile?

28.6

In a random sample of 200 items, 7 items were defective. Estimate the percentage of defective items in the population.

3.5%

The hourly wages of a sample of 130 system analysts are given below. mean=70 mode=77 median=78 range=18 variance=441 Find the coefficient of variation.

30%

The numbers of hours worked (per week) by 400 statistics students are shown below. Number of hours Frequency 0-9 20 10-19 80 20-29 200 30-39 100 What is the midpoint of the fourth class?

34.5

Your retirement account earned the following returns in the past five years: 9%, 4%, 3%, 2%, and 2%. Calculate the mean percentage annual return of your retirement account.

4%

The variance of a sample of 100 observations equals 49. Find the standard deviation of the sample.

7

The numbers of hours worked (per week) by 400 statistics students are shown below. Number of hours Frequency 0-9 60 10-19 100 20-29 160 30-39 80 What is cumulative percent frequency for ≤ 29 hours?

80

Which is the cost of a concert ticket an example of?

?

Suppose the heights of women are approximately normal with a mean of 65 inches and a standard deviation of 3 inches. Suppose that men have a mean height of 69.1 inches with a standard deviation of 2.2 inches. Calculate the z-scores for a 6-foot-tall woman and a 6-foot-tall man. What information does the z-score provide?

Being 6-foot-tall is less extreme for a man than a woman

Which of the following symbols represents the size of the population?

N

A sample of fifteen seven-year-old boys shows their favorite superheroes. Spiderman Captain America Aquaman Batman Spiderman Spiderman Iron Man Superman Spiderman Iron Man Captain America Iron Man Batman Batman Spiderman

Spiderman 5, Batman 3, Iron Man 3, Aquaman 1, Captain America 2, Superman 1

The grades of 10 students in their first management test are shown below. 96 64 97 69 93 69 76 87 85 80 a) Construct a frequency distribution. Let the first class be 60-69. b.) Construct a cumulative frequency distribution. c.) Construct a relative frequency distribution.

a.) Explanation of Frequencies 60 - 69: Grades 64, 69, 69 (Total: 3) 70 - 79: Grades 76 (Total: 1) 80 - 89: Grades 87, 85, 80 (Total: 3) 90 - 99: Grades 96, 97, 93 (Total: 3) b.) 60 - 69: 3 70 - 79: ? 80 - 89: ? 90 - 99: 10 c.) Summary of Relative Frequencies 60 - 69: 3/10 = 0.30 70 - 79: 2/10 = ? 80 - 89: 3/10 = 0.30 90 - 99: 2/10 = ?

A Wall Street Journal (WSJ) subscriber survey asked 46 questions about subscriber characteristics and interests. State whether each of the following questions provides categorical or quantitative data. a.) What is your age? categorical or quantitative b.) Are you married? categorical or quantitative c.) When did you first start reading the WSJ? High school, college, early career, mid-career, late career, or retirement? categorical or quantitative d.) How long have you been in your present job or position? categorical or quantitative e.) What type of vehicle are you considering for your next purchase? Nine response categories include sedan, sports car, SUV, minivan, and so on. categorical or quantitative

a.) quantitative b.) categorical c.) categorical d.) quantitative e.) categorical

An unusually small or unusually large data value is called

an outlier

A student's dormitory room number is an example of

categorical variable

The relative frequency of a class is computed by

dividing the frequency of the class by the total number of elements in the data set.

If a data set has an even number of observations, the median

is the average value of the two middle items when all items are arranged in ascending order.

Statistical inference

is the process of drawing inferences about the population based on the information taken from the sample.

Four people in the management department at a local tech firm have the following reported earnings: $24,000; $54,000; $61,000; $220,000. Which measure of location would best reflect the characteristics of salaries at this company (no calculations are necessary)?

median

In computing the mean of a sample, the value of Σxi is divided by which of the following?

n

Which of the following symbols represents the size of the sample?

n

In a questionnaire, respondents are asked to mark their gender as male, female, or other. The scale of measurement for gender is _____ scale.

nominal

In a cumulative relative frequency distribution, the last class will have a cumulative relative frequency equal to what?

one

A restaurant asks their customers to fill out a questionnaire indicating whether their service was excellent, very good, good, or poor. The rating scale used is an example of the _____ scale.

ordinal

The scale of measurement that is used to rank or order the observation for a variable is called the _____ scale.

ordinal

Eight hundred residents of a city with a population of 240,495 are polled to obtain information on voting intentions in an upcoming city election. What are the eight hundred residents in this study an example of?

sample

In a sample of 1,600 registered voters, 928 or 58% approve of the way the President is doing their job. A political pollster estimates: "Fifty-eight percent of all voters approve of the President." What is this statement an example of?

statistical inference

In a sample of 400 students in a university, 120 or 30% are Business majors. Based on the above information, the school's paper reported that "30% of all the students at the university are Business majors." What is this report an example of?

statistical inference

In a cumulative frequency distribution, the last class will always have a cumulative frequency equal to what?

the total number of elements in the data set

What is the symbol 𝜎2 used to represent?

variance of the population

The measure of dispersion which is not measured in the same units as the original data is the

variance.

Since a sample is a subset of the population, the sample mean _____ the mean of the population.

varies around