Principles of Statistics and Probability (1): Stat-101, Final exam (1432-2)
Majmaa’h University
College of Engineering
1st level (G 381)
Time allowed: 2 hrs
12/7/1432
Answer all the following questions
Question #1:
(5 marks)
The following table gives the frequency distribution of the number of goals scored
by 40 football players in the primary league in Saudi Arabia.
a) Prepare a cumulative frequency distribution.
b) Calculate the cumulative relative frequencies and cumulative percentages for
all classes.
Number of goals Number of players
0 to 3
10
4 to 7
8
8 to 11
11
12 to 15
7
16 to 19
4
Round the values of relative frequencies to 3 decimal places
1
Principles of Statistics and Probability (1): Stat-101, Final exam (1432-2)
Question #2:
(6 marks)
a) The marks of 15 randomly selected students from a class are:
82, 65, 53, 82, 71, 46, 96, 87, 77, 80, 69, 77, 58, 90 and 48.
Find the mode
b) Select the correct answer that describes the following figure:
a) A histogram and frequency curve Skewed to the left
b) A histogram and frequency curve Skewed to the Right
c) A Symmetric histogram and frequency curve
c) The following are the ages of nine employees of a company:
47
28
39
51
33
37
24
33
59
a) Find the values of the three quartiles. Where does the age of 45 falls
in relation to the ages of these employees?
2
Principles of Statistics and Probability (1): Stat-101, Final exam (1432-2)
Question #3:
(6 marks)
The following data are the incomes (in thousands of dollars) for a sample of
12 households.
35 29 44 72
34 64
41 50 54 104 39 58
Construct a box-and-whisker plot. Are the data symmetric or skewed?
Question #4:
(5 marks)
The governorate of Almajmaa’h city wanted to know the distribution of the
computer sets owned by families in the city. A sample of 40 randomly
selected houses from the city produced the following data on the number of
computers owned.
5
1
1
1
1
1
1
2
2
1
1
1
3
2
2
2
3
4
1
1
0
3
2
1
1
1
0
1
1
4
1
2
2
4
1
2
5
2
2
3
Construct the frequency distribution table for these data using singlevalued classes.
3
Principles of Statistics and Probability (1): Stat-101, Final exam (1432-2)
Question #5:
(9 marks)
In a group of people, some are in favor of Civil engineering (F), others are against
(A) and others do not care (D). Three persons are selected at random from this
group and asked whether they are in favor of, or against or they do not care with
Civil engineering. For this experiment
1.
2.
3.
4.
5.
How many simple outcomes are possible?
What is the probability of each simple outcome?
Draw a Venn diagram.
Draw a tree diagram.
List all the outcomes included in each of the following events and find the
probability of each event.
A. All three persons are against civil engineering.
B. At most one person is in favor of civil engineering.
C. Exactly two persons are in favor of civil engineering.
D. At least one person does not care with civil engineering.
4
Principles of Statistics and Probability (1): Stat-101, Final exam (1432-2)
Question #6:
(9 marks)
The table below shows the results of asking 10 female and 20 male employees
about their opinion in having life insurance. Some said they are in favor, some
against and some are undecided.
In Favor Against Undecided
Male
Female
Total
12
4
4
20
5
2
3
15
17
6
7
30
1. Find all marginal probabilities.
2. Find the conditional probabilities:
A. P(Male/Against).
B. P(undecided/female).
C. P(In Favor/male).
D. P(Female/In favor).
Good Luck
Dr. SaMeH Ahmed
5
Total