Download Probability and Statistics

Probability and Statistics
Test 2
Name
Multiple Choice. Circle the best answer.
1. The mean age of two people in a room is 30 years old. A 24 year old walks
into the room. What is the mean age of the tree people?
a. 24
b. 26
c. 28
d. 30
e, None of these
2. Consider the following box plot of blood pressure of 16 patients.
|
108
|
120
|
132
|
144
|
156
Which of the following is true?
a. The mean is about 132
b. The IQR is about 14.
c. The range is about 54.
d. The midrange is about 100.
e. None of the above.
3. Which of the following is most likely to be an actual number in a data set?
a. Mean
b. Standard Deviation
c. Mode
d. Midrange
e. Median
4. Which of one of the following is ordinal data?
a. Car Color
b. Years
c. Cost
d. Letter Grades
8
5. In 1991 the monthly average car production, in thousands, for 20 of
the top auto makers was as follows
(6)
Construct a box plot with inner and outer fences. Find the adjacent
scores and determine which countries have production figures that can
be considered outliers. Classify them as unusual or rare.
6. Final exam scores for 20 students are shown below.
90
71
84
74
78
82
70
83
74
76
64
71
90
76
84
71
(12)
62
91
95
55
Find the mean, median, mode, midrange, 10% trimmed mean and the
population standard deviation.
18
9. The following array shows the average time for waiting in line in a
in minutes.
(8)
2.4
5.1
1.9
.4
5.2
1.8
.6
2.1
3.1
3.1
4.0
4.2
2.9
1.6
a. Constuct a stem and leaf plot.
b. Find the median time.
c. What time is the 80th percentile?
d. What percentile is 1.8 minutes?
10. Give an exmaple of a set of data that is :
(6)
a. qualitative
b. continuous
c. nominal
14
11. Explain the cartoon.
(4)
12 The following table shows computer sales by month for Carl and Angela (6)
a. Construct two five number summaries
for these data.
b. Construct two notched box plots for
Carl and Angela at the 95% confidence
interval.
c. Determine whether or not the difference
In means is statistically significant.
Explain your work.
Sales
Carl Angela
January
February
March
April
May
June
July
August
Septembe
r
October
November
December
34
47
1
15
57
24
20
11
19
51
17
25
39
7
49
62
41
20
50
28
37
6
43
13
10
Extra Credit: What is the smallest number when divided by 3,4, and 5 has
a remainder of 1?