STATS

INTRODUCTION TO STATISTICS (MATO 205)

Hampton University, University College

TEST 1

Name__________________________________ Date__________________

Instructions: You are required to work the questions independently. Do not seek help from

anyone. Follow Hampton University Code of Conduct.

All questions carry equal points.

Fill in the Blank. (1 point each)

The branch of statistics that uses sample information to draw a conclusion about the population is called _________________ ________________________.

Methods of gathering, sorting, summarizing, and presenting data in an enlightening way are called ________________ _____________________.

A numerical description of a population characteristic is referred to as a ______________.

_____________ ___________ indicates how many standard deviations from the mean a particular value lies.

With the ____________level of measurement, the data are sorted into categories consisting of labels or names with no particular order to categories.

The sum of all of the data values divided by the number of data values is called _______________ ________.

____________ ______ is used to estimate the percentage of values within a few standard deviations from the mean.

A circular chart that shows the proportion or percentage that each class represents of the total is called ______________.

The ________________ is the arithmetic mean of the squared deviations from the mean.

The midpoint of a set of values after they have been ordered from the lowest to the highest values is called the ________________.

Decide whether each statement is true or false.

Sample characteristics are called statistics.

(T/F)

Histograms are usually used for qualitative data.

(T/F)

Circle the best answer for each of the following:

Which of the following is an example of descriptive statistics?

In a sample of 1,000 college students, their average I.Q. score is 115.

The average height of all NBA basketball players is 6’7”.

Nine out of 10 doctors recommend non-aspirin pain reliever.

The symbol used to represent the sample standard deviation is

N b) S c) X d) n

The class width for the class 25-29 is:

7 b) 6 c) 5 d) 4

Free Response:

You Must Show Your Work to Earn Full Credit

Below is a data of ACT math scores for a group of college music students. (15 points)

12 15 20 25 32 13 17 20 25 33 23 18 22 25 34

18 21 26 18 21 27 18 22 19 22 13 20 14 19

Complete the stem-and-leaf plot of ACT math scores below:

stem	leaf
1
2
3

Key: 1|2 =12

Use the stem-and –leave plot above to answer the following questions:

What is the lowest math score a student in the class received on the ACT?

What was the highest math score a student in this class received in the ACT?

Which math score occurred most often?

How many students are represented by this information

Consider these data on the selling prices ($000) of homes in the city of Warren, Pennsylvania, last year. (15 points)

Selling Price ($000)	Frequency
120 up to 150	4
150 up to 180	18
180 up to 210	30
210 up to 240	20
240 up to 270	17
270 up to 300	10
300 up to 330	6

How many homes were sold last year?

How many homes sold for less than $210,000?

What is the relative frequency for the $210 up to $240 class?

What is the midpoint of the $150 up to $180 class?

What were the lowest and highest selling prices?

Given the frequency table of ages of taste-test participants (in years) below, calculate the relative frequency for each class and construct a relative frequency histogram. (20 points)

Class	Frequency	Class Boundaries	Relative Frequency
15-19	7	14.5-19.5	23%
20-24	8
25-29	10
30-34	2
35-39	3
Total	30

Construct Relative Frequency Histogram of Ages of Taste-Test Participants below

Dave’s Automatic Door installs automatic garage door openers. The following list indicates the number of minutes needed to install a sample of 10 door openers: (20 points)

28 32 24 46 44 40 54 38 32 42

Complete the table of values below.

28
32
24
46
44
40
54
38
32
42
Total =

Use the table of values above to answer the following questions:

What is the mean number of minutes needed to install door openers?

What is the median number of minutes needed to install door openers?

What is the range of the number of minutes needed to install door openers?

What is the standard deviation of the minutes required to install door openers?

What are the minimum, first quartile, median, third quartile, maximum, interquartile range, and range of the data set below? Make a box-and-whisker plot. (15 points)

90 47 88 53 59 72 68 62 79