Statistics-If you flip a coin three times, the possible outcomes are HHH, HHT

Question 1 of 40

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 that at least two heads occur consecutively?

A. 1/8
B. 3/8
C. 5/8
D. 6/8
Question 2 of 40	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 3 of 40	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 4 of 40	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 5 of 40	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 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 7 of 40	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 8 of 40	2.5 Points

Suppose you have an
extremely unfair coin: the probability of a head is 1/5, and the probability of
a tail is 4/5. If you toss the coin 40 times, how many heads do you expect to
see?

A. 8
B. 6
C. 5
D. 4
Question 9 of 40	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 10 of 40	2.5 Points

Suppose you pay $1.00 to
roll a fair die with the understanding that you will get back $3.00 for rolling
a 5 or a 2, nothing otherwise. What is your expected value?

A. $1.00
B. $0.00
C. $3.00
D. −$1.00
Question 11 of 40	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 12 of 40	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 13 of 40	2.5 Points

The probability that
Luis will pass his statistics test is 0.94. Find the probability that he will
fail his statistics test.

A. 0.02
B. 0.05
C. 0.94
D. 0.06
Question 14 of 40	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 15 of 40	2.5 Points

Based on meteorological records,
the probability that it will snow in a certain town on January 1st is 0.413.
Find the probability that in a given year it will not snow on January 1st in
that town.

A. 0.345
B. 0.425
C. 0.587
D. 0.592
Question 16 of 40	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 17 of 40	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 18 of 40	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 19 of 40	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.
Question 20 of 40	2.5 Points

Suppose you buy 1 ticket
for $1 out of a lottery of 1000 tickets where the prize for the one winning
ticket is to be $500. What is your expected value?

A. $0.00
B. −$0.40
C. −$1.00
D. −$0.50
Question 21 of 40	2.5 Points

Which point below would
be an outlier if it were on the following graph?

A. (25, 20)
B. (5, 12)
C. (7, 5)
D. (5, 3)
Question 22 of 40	2.5 Points

The scatter plot and
best-fit line show the relation between the price per item (y) and the
availability of that item (x) in arbitrary units. The correlation coefficient
is -0.95. Determine the amount of variation in pricing explained by the variation
in availability.

A. 5%
B. 10%
C. 95%
D. 90%
Question 23 of 40	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 24 of 40	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 25 of 40	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 26 of 40	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 27 of 40	2.5 Points

The scatter plot and
best-fit line show the relation among the number of cars waiting by a school
(y) and the amount of time after the end of classes (x) in arbitrary units. The
correlation coefficient is -0.55. Determine the amount of variation in the
number of cars not explained by the variation time after school.

A. 55%
B. 70%
C. 30%
D. 45%
Question 29 of 40	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 28 of 40	2.5 Points

Select the best estimate
of the correlation coefficient for the data depicted in the scatter diagram.

A. -0.9
B. 0.1
C. 0.5
D. 0.9
Question 30 of 40	2.5 Points

A population proportion
is to be estimated. Estimate the minimum sample size needed to achieve a margin
of error E = 0.01with a 95% degree of confidence.

A. 7,000
B. 8,000
C. 9,000
D. 10,000
Question 31 of 40	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 32 of 40	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 33 of 40	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 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 35 of 40	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 36 of 40	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 37 of 40	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 38 of 40	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 39 of 40	2.5 Points

The graph shows a measure
of fitness (y) and miles walked weekly. Identify the probable cause of the
correlation.