HW: 5.1 Basic Concepts of Probability Assignment
1) Fill in the blank with the appropriate word or phrase.
If an event cannot occur, its probability is
2) Fill in the blank with the appropriate word or phrase.
If an event is certain to occur, its probability is
3) Fill in the blank with the appropriate word or phrase.
The collection of all possible outcomes of a probability experiment is called
4) Fill in the blank with the appropriate word or phrase.
An outcome or collection of outcomes from a sample space is called
5) Assume that a fair die is rolled. The sample space is {1, 2, 3, 4, 5, 6}, and all the outcomes are
equally likely. Find P(0). Express your answer in exact form.
6) Assume that a fair die is rolled. The sample space is {1, 2, 3, 4, 5, 6}, and all the outcomes are
equally likely. Find P(Greater than 2). Express your answer in exact form.
7) Assume that a coin is tossed twice. The coin may not be fair. The sample space consists of the
outcomes {HH, HT, TH, TT}.
8) How probable is it? Someone computes the probabilities of several events. The probabilities are
listed below. Select the best verbal description for each probability.
9) Who will you vote for? In a survey of 500 likely voters in a certain city, 295 said that they planned
to vote to reelect the incumbent mayor.
10) True-false exam: A section of exam contains four true-false questions. A completed exam paper
is selected at random, and the four answers are recorded. Round your answers to four decimal
places if necessary.
11) Empirical Method: A die is rolled 550 times. On 85 of those rolls, the die comes up 6. Use the
Empirical method to approximate the probability that the die comes up 6. Round your answer to
four decimal places as necessary.
12) More pitching: A baseball pitcher threw 3414 pitches during part of a recent season. Of these,
1935 were thrown with no strikes on the batter, 921 were thrown with one, and 558 were
thrown with two strikes.
13) Get an education: A survey asked 32, 126 people how much confidence they had in educational
institutions. The results were as follows. Round your answers to four decimal places if necessary.
Part
1
of
3
@
10026+4285
=
14308
|
14308/32126
(a)
What
is
the
probability
that a
sampled
person
has
either
a
great
deal
or
hardly
any
confidence
in
educational
institutions?
The
probability
that a
sampled
person
has
either
a
great
deal
or
hardly
any
confidence
in
educational
institutions
i:
Part
2
of
3
Q
(b)
Assume
this
is
a
simple
random
sample
from
a
population.
Use
the
Empirical
Method
to
estimate
the
probability
that
a
person
has
hardly
any
confidence
in
educational
institutions.
4282/32126
Using
the
Empirical
Method
the
probability
is
approximately
Part
3
of
3
17818/32126
=
0.5546
an)
(c)
If
we
use
a
cutoff
of
0.05,
is
it
unusual
for
someone
to
have
some
confidence
in
educational
institutions?
is
higher
than
0.05,
so
it’s
not
unusual
for
someone
to
have
Based
on
a
cutoff
of
0.05,
it
|is
not
vy
unusual
for
someone
to
have
some
confidence
in
educational
institutions.
some
confidence
