Sata HW
stat week four
QUESTION 1
The standard normal distribution is a normal probability distribution that has a mean of and
a standard deviation of , and the total area under its density curve is equal to .
QUESTION 2
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading less than -.25 in degrees Celsius. (up to four decimal place, please)
QUESTION 3
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading greater than .25 in degrees Celsius. (up to four decimal place, please)
QUESTION 4
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading greater than -1.05 in degrees Celsius. (up to four decimal place, please)
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading less than 1.93 in degrees Celsius. (up to four decimal place, please)
QUESTION 6
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading between -2.67 and 1.28 in degrees Celsius. (up to four decimal place, please)
QUESTION 7
Assume that the readings on scietific thermometers are normally distributed with a mean of 0 0C and a standard deviation of 1 0C . A thermometer is randomly selected and tested. Find the probability of the reading between 2.70 and 3.13 in degrees Celsius. (up to four decimal place, please)
QUESTION 8
For a standard normal distribution, find the percentage of data that are more than 2 standard deviations away from the mean. (up to two decimal place, please)
QUESTION 9
QUESTION 10
Assume that human body temperatures are normally distributed with a mean of 98.20 0F and a standard deviation of 0.62 0F. Physicians want to select a minimum temperature for requiring further medical tests. what should that temperature be, if we want only 5% of healthy people to exceed it? (Such a result is a false positive, meaning that the test result is positive, but the subject is not really sick.) (up to one decimal place, please)
QUESTION 11
Assume that the heights of women are normally distributed with a mean given by 63.6 inches and a standard deviation given by 2.5 inches. The Beanstalk club, a social organization for tall people, has a requirement that women must be at least 70 inches tall. What percentage of women meet that requirement? (up to four decimal place, please)
QUESTION 12
Assume that the heights of women are normally distributed with a mean given by 63.6 inches and a standard deviation given by 2.5 inches. The U.S. Army requires women's heights to be between 58 inches and 80 inches. What percentage of women meet that requirement? (up to four decimal place, please)
QUESTION 13
The intelligence quotient (IQ) is based on a test of aptitude and is often used as a measure of an individual’s intelligence. The distribution of IQ scores is approximately normally distributed with mean 100 and standard deviation 15. What is the z-value of 80? (up to three decimal place, please)
QUESTION 14
The distribution of IQ scores is approximately normally distributed with mean 100 and standard deviation 15. What is the probability to have an IQ score 140 or above?
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a. |
0.9962 |
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b. |
0.9924 |
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c. |
0.0076 |
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d. |
0.0038 |
QUESTION 15
The distribution of IQ scores is approximately normally distributed with mean 100 and standard deviation 15. What is the probability to have an IQ score between 110 and 120?
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a. |
.7486 |
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b. |
.9082 |
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c. |
.0918 |
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d. |
.1596 |
QUESTION 16
Five numbers are given: 85, 79, 82, 73, 78. Assume that samples of size 2 are randomly selected with replacement from the above population of five numbers. Find the mean of the sampling distribution.
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a. |
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b. |
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c. |
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d. |
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QUESTION 17
Five numbers are given: 85, 79, 82, 73, 78. Assume that samples of size 2 are randomly selected with replacement from the above population of five numbers. Calculate the standard deviation of the sampling distribution of sample mean. (up to four decimal place, please)
QUESTION 18
Assume that men's weights are normally distributed with a mean of 172 lb and a standard deviation of 29 lb. If one man is randomly selected, find the probability that his weight is less than 167 lb.(up to four decimal place, please)
QUESTION 19
Assume that men's weights are normally distributed with a mean of 172 lb and a standard deviation of 29 lb. If 36 man is randomly selected, find the probability that they have a mean weight less than 167 lb.(up to four decimal place, please)
QUESTION 20
Assume that men's weights are normally distributed with a mean of 172 lb and a standard deviation of 29 lb. If 4 man is randomly selected, find the probability that they have a mean weight between 160 lb and 180 lb.(up to four decimal place, please)
STAT WEEK FOUR
QUESTION 1
The
standard
normal
distribution
is
a
normal
probability
distribution
that
has
a
mean
of
and
a
standard
deviation
of
,
and
the
total
area
under
its
density
curve
is
equal
to
.
QUESTION 2
Assume
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
less
than
-
.25
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
QUESTION 3
Assume
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
greater
than
.25
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
QUESTION 4
Assume
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
greater
than
-
1.05
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
Assume
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
less
than
1.93
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
QUESTION 6
Assum
e
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
between
-
2.67
and
1.28
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
QUESTION 7
Assume
that
the
readings
on
scietific
thermometers
are
normally
distributed
with
a
mean
of
0
0
C
and
a
standard
deviation
of
1
0
C
.
A
thermometer
is
randomly
selected
and
tested.
Find
the
probability
of
the
reading
between
2.70
and
3.13
in
degrees
Celsius.
(up
to
four
decimal
place,
please)
QUESTION 8
For a standard normal distribution, find the percentage of data that are more than 2 standard deviations away from
the mean. (up to two decimal place, please)
STAT WEEK FOUR
QUESTION 1
The standard normal distribution is a normal probability distribution that has a mean of
and
a standard deviation of
, and the total area under its density curve is equal to
.
QUESTION 2
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading less than -.25
in degrees Celsius. (up to four decimal place, please)
QUESTION 3
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading greater than
.25 in degrees Celsius. (up to four decimal place, please)
QUESTION 4
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading greater than -
1.05 in degrees Celsius. (up to four decimal place, please)
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading less than 1.93
in degrees Celsius. (up to four decimal place, please)
QUESTION 6
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading between -2.67
and 1.28 in degrees Celsius. (up to four decimal place, please)
QUESTION 7
Assume that the readings on scietific thermometers are normally distributed with a mean of 0
0
C and a standard
deviation of 1
0
C . A thermometer is randomly selected and tested. Find the probability of the reading between 2.70
and 3.13 in degrees Celsius. (up to four decimal place, please)
QUESTION 8
For a standard normal distribution, find the percentage of data that are more than 2 standard deviations away from
the mean. (up to two decimal place, please)