MA260.2.1 Statistical Analysis ILog Out   Online Exam 6_06   Return to Assessment List     Part 1 of 2 -30.0/ 50.0 Points     Question 1 of 400.0/ 2.5...

MA260.2.1 Statistical Analysis ILog Out

Online Exam 6_06

Return to Assessment List

Part 1 of 2 -30.0/ 50.0 Points

Question 1 of 400.0/ 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 2 of 402.5/ 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 3 of 402.5/ 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 4 of 402.5/ 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 5 of 402.5/ 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 6 of 400.0/ 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 7 of 402.5/ 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 8 of 402.5/ 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 402.5/ 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 10 of 400.0/ 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 11 of 402.5/ 2.5 Points

A bag contains four chips of which one is red, one is blue, one is green, and one is yellow. A chip is selected at random from the bag and then replaced in the bag. A second chip is then selected at random. Make a list of the possible outcomes (for example, RB represents the outcome red chip followed by blue chip) and use your list to determine the probability that the two chips selected are the same color. (Hint: There are 16 possible outcomes.)

A. 1/4

B. 3/4

C. 2/16

D. 3/16

Question 12 of 400.0/ 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 13 of 400.0/ 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 14 of 402.5/ 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 15 of 400.0/ 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 16 of 402.5/ 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 two tails?

A. 1/2

B. 2/3

C. 3/4

D. 4/9

Question 17 of 402.5/ 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 18 of 402.5/ 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 19 of 400.0/ 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 20 of 400.0/ 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

Part 2 of 2 -0.0/ 50.0 Points

Question 21 of 400.0/ 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 400.0/ 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 23 of 400.0/ 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 24 of 400.0/ 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 25 of 400.0/ 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 400.0/ 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 27 of 400.0/ 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 28 of 400.0/ 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 29 of 400.0/ 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 30 of 400.0/ 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 31 of 400.0/ 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 32 of 400.0/ 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 33 of 400.0/ 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 34 of 400.0/ 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 35 of 400.0/ 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 36 of 400.0/ 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 37 of 400.0/ 2.5 Points

Of the 6796 students in one school district, 1537 cannot read up to grade level. Among a sample of 812 of the students from this school district, 211 cannot read up to grade level. Find the sample proportion of students who cannot read up to grade level.

A. 0.14

B. 0.26

C. 211

D. 0.23

Question 38 of 400.0/ 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.