Stat 101 – Sheet 7
King Saud University
Almajmaa’h Engineering College
STAT 101
1430/2009
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Sheet (7)
Probability
1. Define the following terms: experiment, outcome, sample space, simple
event, and compound event.
2. List the simple events for each of the following statistical experiments in a
sample space S.
a. One roll of a die
b. Three tosses of a coin
c. One toss of a coin and one roll of a die.
3. A box contains three items that are labeled A, B, and C. two items are
selected at random (without replacement) from this box. List all the
possible outcomes for this experiment. Write the sample space S.
4. Two students are randomly selected from a statistics class, and it is
observed whether or not they suffer from math anxiety. How many total
outcomes are possible? Draw a tree diagram for this experiment. Draw a
Venn diagram.
5. A test contains two multiple-choice questions. If a student makes a
random guess to answer each question, how many outcomes are
possible? Depict all these outcomes in a Venn diagram. Also draw a tree
diagram for this experiment. (Hint: consider two outcomes for each
question – either the answer is correct or it is wrong.)
Dr. SaMeH
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Stat 101 – Sheet 7
6. Refer to Problem 4, list the outcomes included in each of the following
events. Indicated which are simple and which compound events are.
a. Both students suffer from math anxiety.
b. Exactly one student suffers from math anxiety.
c. The first student does not suffer and the second suffers from math
anxiety.
d. None of the students suffers from math anxiety.
7. Refer to Problem 5, list the outcomes included in each of the following
events and mention which are simple and which compound events are.
a.
b.
c.
d.
Both answers are correct.
At most one answer is wrong.
The first answer is correct and the second is wrong.
Exactly one answer is wrong.
8. In a group of people, some are in favor of football and others are against.
Two persons are selected at random from this group and asked whether
they are in favor of or against football. How many distinct outcomes are
possible? Draw a Venn diagram and a tree diagram for this experiment.
List all the outcomes included in each of the following events and mention
whether they are simple or compound events.
a. Both persons are in favor of football.
b. At most one person is against football.
c. Exactly one person is in favor of football.
You are required to solve all the problems and submit the answers by email in
one week time after the lesson.
Dr. SaMeH
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