online exam

Part 1 of 2 – 42.5/
50.0 Points

Question 1 of 40
2.5/ 2.5 Points
Joe dealt 20 cards from a standard 52-card deck, and the
number of red cards exceeded the number of black cards by 8. He reshuffled the
cards and dealt 30 cards. This time, the number of red cards exceeded the
number of black cards by 10. Determine which deal is closer to the 50/50 ratio
of red/black expected of fairly dealt hands from a fair deck and why.
A. The first series
is closer because 1/10 is farther from 1/2 than is 1/8.
B. The series closer
to the theoretical 50/50 cannot be determined unless the number of red and
black cards for each deal is given.
C. The second series
is closer because 20/30 is closer to 1/2 than is 14/20.
D. The first series
is closer because the difference between red and black is smaller than the
difference in the second series.

Question 2 of 40
2.5/ 2.5 Points
Sammy and Sally each carry a bag containing a banana, a
chocolate bar, and a licorice stick. Simultaneously, they take out a single
food item and consume it. The possible pairs of food items that Sally and Sammy
consumed are as follows.

chocolate bar – chocolate bar

licorice stick – chocolate bar

banana – banana

chocolate bar – licorice stick

licorice stick – licorice stick

chocolate bar – banana

banana – licorice stick

licorice stick – banana

banana – chocolate bar

Find the probability that no chocolate bar was eaten.

A. 4/9
B. 5/9
C. 7/9
D. 5/8

Question 3 of 40
2.5/ 2.5 Points
In a poll, respondents were asked whether they had ever been
in a car accident. 220 respondents indicated that they had been in a car
accident and 370 respondents said that they had not been in a car accident. If
one of these respondents is randomly selected, what is the probability of
getting someone who has been in a car accident? Round to the nearest
thousandth.
A. 0.384
B. 0.380
C. 0.373
D. 0.370

Question 4 of 40
2.5/ 2.5 Points
A sample space consists of 46 separate events that are
equally likely. What is the probability of each?
A. 1/24
B. 1/46
C. 1/32
D. 1/18

Question 5 of 40
2.5/ 2.5 Points
A committee of three people is to be formed. The three
people will be selected from a list of five possible committee members. A
simple random sample of three people is taken, without replacement, from the
group of five people. Using the letters A, B, C, D, E to represent the five
people, list the possible samples of size three and use your list to determine
the probability that B is included in the sample. (Hint: There are 10 possible
samples.)
A. 0.6
B. 0.4
C. 0.7
D. 0.8

Question 6 of 40
2.5/ 2.5 Points
If a person is randomly selected, find the probability that
his or her birthday is not in May. Ignore leap years. There are 365 days in a
year. Express your answer as a fraction.
A. 335/365
B. 334/365
C. 336/365
D. 30/365

Question 7 of 40
0.0/ 2.5 Points
A study of 600 college students taking Statistics 101
revealed that 54
students received the grade of A. Typically 10% of the class
gets an A.
The difference between this group of students and the
expected value is
not significant at the 0.05 level. What does this mean in
this case?
A. The probability
that the difference occurred due to chance is less than 0.05.
B. The probability
of getting an A is 10% and only 9% got an A in this
study. The difference is less than 5% so it is not
significant.
C. There is not
enough information to make any conclusion.
D. The probability
that the difference occurred due to chance is more than 0.05.

Question 8 of 40
0.0/ 2.5 Points
A 28-year-old man pays $125 for a one-year life insurance
policy with coverage of $140,000. If the probability that he will live through
the year is 0.9994, to the nearest dollar, what is the man’s expected value for
the insurance policy?
A. $139,916
B. −$41
C. $84
D. −$124

Question 9 of 40
2.5/ 2.5 Points
If you flip a coin three times, the possible outcomes are
HHH, HHT, HTH,
HTT, THH, THT, TTH, TTT. What is the probability of getting
at least one head?
A. 4/9
B. 5/6
C. 7/8
D. 5/8

Question 10 of 40
2.5/ 2.5 Points
The data set represents the income levels of the members of a
country club. Estimate the probability that a randomly selected member earns at
least $98,000.

112,000 126,000 90,000 133,000 94,000 112,000 98,000 82,000
147,000 182,000 86,000 105,000

140,000 94,000 126,000 119,000 98,000 154,000 78,000 119,000

A. 0.4
B. 0.6
C. 0.66
D. 0.7

Question 11 of 40
2.5/ 2.5 Points
A die with 12 sides is rolled. What is the probability of
rolling a number less than 11? Is this the same as rolling a total less than 11
with two six-sided dice? Explain.
A. 2/6
B. 3/6
C. 4/6
D. 5/6

Question 12 of 40
2.5/ 2.5 Points
Suppose you have an extremely unfair die: The probability of
a 6 is 3/8, and the probability of each other number is 1/8. If you toss the
die 32 times, how many twos do you expect to see?
A. 2
B. 4
C. 3
D. 5

Question 13 of 40
2.5/ 2.5 Points
A bag contains 4 red marbles, 3 blue marbles, and 7 green
marbles. If a marble is randomly selected from the bag, what is the probability
that it is blue?
A. 2/11
B. 3/11
C. 5/14
D. 3/14

Question 14 of 40
2.5/ 2.5 Points
A study of two types of weed killers was done on two
identical weed plots. One weed killer killed 15% more weeds than the other.
This difference was significant at the 0.05 level. What does this mean?
A. The improvement
was due to the fact that there were more weeds in one study.
B. The probability
that the difference was due to chance alone is greater than 0.05.
C. The probability
that one weed killer performed better by chance alone is less than 0.05.
D. There is not
enough information to make any conclusion.

Question 15 of 40
2.5/ 2.5 Points
On a multiple choice test, each question has 6 possible
answers. If you make a random guess on the first question, what is the probability
that you are correct?
A. 1/5
B. 1/6
C. 1/4
D. 2/5

Question 16 of 40
2.5/ 2.5 Points
The distribution of B.A. degrees conferred by a local
college is listed below, by major.

Major
Frequency
English 2073

Mathematics
2164

Chemistry
318

Physics
856

Liberal Arts
1358

Business
1676

Engineering
868

9313

What is the probability that a randomly selected degree is
not in Business?

A. 0.7800
B. 0.8200
C. 0.8300
D. 0.9200

Question 17 of 40
2.5/ 2.5 Points
In the first series of rolls of a die, the number of odd
numbers exceeded the number of even numbers by 5. In the second series of rolls
of the same die, the number of odd numbers exceeded the number of even numbers
by 11. Determine which series is closer to the 50/50 ratio of odd/even expected
of a fairly rolled die.
A. The second series
is closer because the difference between odd and even numbers is greater than
the difference for the first series.
B. The first series
is closer because the difference between odd and even numbers is less than the
difference for the second series.
C. Since 1/2 >
1/5 > 1/11, the first series is closer.
D. The series closer
to the theoretical 50/50 cannot be determined unless the total number of rolls
for both series is given.

Question 18 of 40
2.5/ 2.5 Points
Suppose you have an extremely unfair coin: the probability
of a head is 1/3 and the probability of a tail is 2/3. If you toss the coin 72
times, how many heads do you expect to see?
A. 12
B. 22
C. 24
D. 26

Question 19 of 40
0.0/ 2.5 Points
Jody checked the temperature 12 times on Monday, and the
last digit of the temperature was odd six times more than it was even. On
Tuesday, she checked it 18 times and the last digit was odd eight times more
than it was even. Determine which series is closer to the 50/50 ratio of
odd/even expected of such a series of temperature checks.
A. The Monday series
is closer because 1/6 is closer to 1/2 than is 1/8.
B. The Monday series
is closer because 6/12 is closer to 0.5 than is 8/18.
C. The Tuesday
series is closer because the 13/18 is closer to 0.5 than is 9/12.
D. The series
closest to the theoretical 50/50 cannot be determined without knowing the
number of odds and evens in each series.

Question 20 of 40
2.5/ 2.5 Points
A study of students taking Statistics 101 was done. Four
hundred students who studied for more than 10 hours averaged a B. Two hundred
students who studied for less than 10 hours averaged a C. This difference was
significant at the 0.01 level. What does this mean?
A. The probability
that the difference was due to chance alone is greater than 0.01.
B. There is less
than a 0.01 chance that the first group’s grades were better by chance alone.
C. The improvement
was due to the fact that more people studied.
D. There is not
enough information to make any conclusion.

Part 2 of 2 – 35.0/
50.0 Points

Question 21 of 40
0.0/ 2.5 Points
Write possible coordinates for the single outlier such that
it would no longer be an outlier.

A. (23, 18)
B. (20, 5)
C. (15, 15)
D. (12, 15)

Question 22 of 40
2.5/ 2.5 Points
A random sample of 30 households was selected from a
particular neighborhood. The number of cars for each household is shown below.
Estimate the mean number of cars per household for the population of households
in this neighborhood. Give the 95% confidence interval.

A. 1.14 to 1.88
B. 1.12 to 1.88
C. 1.12 to 1.98
D. 1.14 to 1.98

Question 23 of 40
2.5/ 2.5 Points
Which graph has two groups of data, correlations within each
group, but no correlation among all the data?

A.

B.

C.

D.

Question 24 of 40
2.5/ 2.5 Points
Sample size = 400, sample mean = 44, sample standard
deviation = 16. What is the margin of error?
A. 1.4
B. 1.6
C. 2.2
D. 2.6

Question 25 of 40
0.0/ 2.5 Points
A researcher wishes to estimate the proportion of college
students who cheat on exams. A poll of 560 college students showed that 27% of
them had, or intended to, cheat on examinations. Find the 95% confidence
interval.
A. 0.2323 to 0.3075
B. 0.2325 to 0.3075
C. 0.2325 to 0.3185
D. 0.2323 to 0.3185

Question 26 of 40
0.0/ 2.5 Points
A sample of 64 statistics students at a small college had a
mean mathematics ACT score of 28 with a standard deviation of 4. Estimate the
mean mathematics ACT score for all statistics students at this college. Give
the 95% confidence interval.
A. 28.0 to 30.0
B. 25.0 to 27.0
C. 29.0 to 31.0
D. 27.0 to 29.0

Question 27 of 40
0.0/ 2.5 Points
Suggest the cause of the correlation among the data.

The graph shows strength of coffee (y) and number of scoops
used to make 10 cups of coffee (x). Identify the probable cause of the
correlation.

A.
The variation in the x variable is a direct cause of the
variation in
the y variable.

B. There is no
correlation between the variables.
C. The correlation
is due to a common underlying cause.
D. The correlation
between the variables is coincidental.

Question 28 of 40
0.0/ 2.5 Points
A researcher wishes to estimate the proportion of college
students who cheat on exams. A poll of 490 college students showed that 33% of
them had, or intended to, cheat on examinations. Find the margin of error for
the 95% confidence interval.
A. 0.0432
B. 0.0434
C. 0.0425
D. 0.0427

Question 29 of 40
2.5/ 2.5 Points
Among a random sample of 150 employees of a particular
company, the mean commute distance is 29.6 miles. This mean lies 1.2 standard
deviations above the mean of the sampling distribution. If a second sample of
150 employees is selected, what is the probability that for the second sample,
the mean commute distance will be less than 29.6 miles?
A. 0.8849
B. 0.5
C. 0.1131
D. 0.1151

Question 30 of 40
2.5/ 2.5 Points
Among a random sample of 500 college students, the mean
number of hours worked per week at non-college related jobs is 14.6. This mean
lies 0.4 standard deviations below the mean of the sampling distribution. If a
second sample of 500 students is selected, what is the probability that for the
second sample, the mean number of hours worked will be less than 14.6?

A. 0.5
B. 0.6179
C. 0.6554
D. 0.3446

Question 31 of 40
2.5/ 2.5 Points
Select the best estimate of the correlation coefficient for
the data depicted in the scatter diagram.

A. 0.60
B. -0.97
C. 0.10
D. -0.60

Question 32 of 40
2.5/ 2.5 Points
A researcher wishes to estimate the mean amount of money
spent per month on food by households in a certain neighborhood. She desires a
margin of error of $30. Past studies suggest that a population standard
deviation of $248 is reasonable. Estimate the minimum sample size needed to
estimate the population mean with the stated accuracy.
A. 274
B. 284
C. 264
D. 272

Question 33 of 40
2.5/ 2.5 Points
30% of the fifth grade students in a large school district
read below grade level. The distribution of sample proportions of samples of
100 students from this population is normal with a mean of 0.30 and a standard
deviation of 0.045. Suppose that you select a sample of 100 fifth grade
students from this district and find that the proportion that reads below grade
level in the sample is 0.36. What is the probability that a second sample would
be selected with a proportion less than 0.36?
A. 0.8932
B. 0.8920
C. 0.9032
D. 0.9048

Question 34 of 40
2.5/ 2.5 Points
Select the best fit line on the scatter diagram below.

A. A
B. B
C. C
D. All of the lines
are equally good

Question 35 of 40
2.5/ 2.5 Points
Select the best fit line on the scatter diagram below.

A. A
B. B
C. C
D. None of the lines
is the line of best fit

Question 36 of 40
2.5/ 2.5 Points
Monthly incomes of employees at a particular company have a
mean of $5954. The distribution of sample means for samples of size 70 is
normal with a mean of $5954 and a standard deviation of $259. Suppose you take
a sample of size 70 employees from the company and find that their mean monthly
income is $5747. How many standard deviations is the sample mean from the mean
of the sampling distribution?
A. 0.8 standard
deviations above the mean
B. 0.8 standard
deviations below the mean
C. 7.3 standard deviations
below the mean
D. 207 standard
deviations below the mean

Question 37 of 40
2.5/ 2.5 Points
Select the best estimate of the correlation coefficient for
the data depicted in the scatter diagram.

A. -0.9
B. 0.9
C. 0.5
D. -0.5

Question 38 of 40
0.0/ 2.5 Points
Which line of the three shown in the scatter diagram below
fits the data best?

A. A
B. B
C. C
D. All the lines are
equally good

Question 39 of 40
2.5/ 2.5 Points
The graph shows a measure of fitness (y) and miles walked
weekly. Identify the probable cause of the correlation.

A. The correlation
is coincidental.
B. There is a common
underlying cause of the correlation.
C. There is no
correlation between the variables.
D. Walking is a
direct cause of the fitness.

Question 40 of 40
2.5/ 2.5 Points
In a poll of 400 voters in a certain state, 61% said that
they opposed a voter ID bill that might hinder some legitimate voters from
voting. The margin of error in the poll was reported as 4 percentage points
(with a 95% degree of confidence). Which statement is correct?
A.
The reported margin of error is consistent with
the sample size.
B. There is not
enough information to determine whether the margin of error is consistent with
the sample size.
B.
C. The
sample size is too small to achieve the stated margin of error.
C.
D. For
the given sample size, the margin of error should be smaller than stated.