# 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.