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A bag has 5 blue pens, 2 red pens, 2 green pens and 1 yellow pen. What is the probability of drawing 2 successive red pens? 1/5 1/45 1/90 2/15

1/45

A bag has 5 blue pens, 2 red pens, 2 green pens and 1 yellow pen. What is the probability of drawing 2 successive red pens? 1/5 1/45 1/90 2/15

1/45 Explanation: total = 10 2 red pens 2/10 * 1/9 = 2/ 90 1/45

1/6

Three coins are tossed. What is the probability of NO tails? 1/8 1/4 1/16 1/2

1/8

Mark conducted a math test and the mean result of his students was 73, with a variance of 49 (standard deviation = 7). The grade excellent was achieved by all students who scored 86 points or higher. Assume that the grades are normally distributed and the class has 100 students. How many students managed to get an excellent grade? 3 6 12 17

3 Explanation: The standard deviation is the square root of the variance so the standard deviation is 7. The z-score is: z = 86 - 73 / 7 = 1.86 From the z-score table, this gives 0.96856. This means that 96.9% of students are to the left of this value or 3.1 % are to the right (1 - 0.969). As you can't have a part of a student, 3% of the 100 students or 3 students scored an excellent (over 86 points).

Dr. McLaughlin is studying the prevalence of parvovirus in shelter dogs. He takes a random sample of dogs and he intends to find a 95% confidence interval for the population mean. With which of the following sample sizes would he be able to better estimate the population mean? 300 dogs 250 dogs 30 dogs 25 dogs

300 dogs

In a college class, the average IQ is 115. Assume that the distribution is normal and that the standard deviation is 15. What percentage of the class has an IQ between 105 and 130? (Use a Z table, not provided. Please use the link in the chapter description or do a search.) 28% 59% 54% 45%

59% Explantion: Z=(105-115)/15=—10/15=-2/3=—.66 Again z=(130-115)/15=15/15=1 Now, p(105<x<130)=p(—.66<z<1) =P(—.66<z<0)+p(0<z<1) =.5867 Required percentage=58.67

The probability distribution for x is presented in the following table. What is the probability that x is greater than or equal to 3? 60% 50% 40% 90%

60% Explanation: (P>= 3) (P = 3) + (P = 4) 0.1 + 0.5 = 0.6 = 60%

The stem and leaf plot shown below shows the number of aces hit by the world's best tennis players in the past month. What percentage of players hit more than 29 aces? 67% 70% 60% 33%

67%

Russell is a history teacher who recently held an exam in his class. The mean score result is 65, while the standard deviation was 20. Assume that the scores are normally distributed. If a student's z-score was 1.5, how many points did he score on the exam? 30 75 95 65

95 Explanation: z-score = (data point - mean ) / standard deviation 1.5 = (x - 65) / 20

Measures of Central Tendency

Mean, Median and Mode

It has been reported that the mean score for a student who takes the certain test is 80 with a standard deviation of 9. For a random sample of 100 students, what is the standard error? a) 0.9 b) 0.8 c) 0.6 d) 0.5

a) 0.9

Construct a 95% confidence interval for the following data set: Round to the nearest whole number. Sample mean: 1,245 Sample standard deviation: 38 Sample size: 16 a) 1,228 to 1,262 b) 1,248 to 1,542 c) 1,364 to 1,487 d) 1,215 to 1,378

a) 1,228 to 1,262 Explanation: x-bar = 1245 s = 38 n = 16 95% confidence interval sx-bar = s / √ n = 38 / √16 = 9.5 From the Critical Values of the t Distribution Table: 15 or (n - 1) degrees of freedom for 95% = 1.75 = t x-bar ± t * sx-bar 1245 ± 1.75(9.5) = 16.6 1245 - 16.6 = 1228.4 ≈ 1228 1245 + 16.6 = 1261.6 ≈ 1262

A bag of candy which has 100 pieces of candy has 15 yellow pieces, 17 green pieces, 18 red pieces, 20 blue pieces and 30 orange pieces. What is the probability that you will draw an orange or blue piece? a) 1/2 b) 2/3 c) 3/5 d) 2/100

a) 1/2 Explanation: Probability of getting an orange piece = 30/100 Probability of getting a blue piece = 20/100 Add these together to get the probability of getting orange or blue : 30/100 + 20/100 = 50/100 = 1/2 Or, you could add them first: Probability of getting orange or blue = (30 + 20) out of 100 possible pieces = (30 + 20)/100 = 50/100 = 1/2

On a 20-sided die, each side shows a number from 1-20. What is the probability that the sum of the numbers shown will be 6 when rolling two? a) 1/80 b) 1/6 c) 395/400 d) 1/400

a) 1/80

A researcher is conducting studies about the average weight and height of college students. Their height is in centimeters and their weight is in pounds. Their names were substituted with numbers in order to conceal their identities. What is the standard deviation of their height? a) 12.13 b) 13.83 c) 11.25 d) 14.26

a) 12.13

Suppose that you take 160 simple random samples from a population and that, for each sample, you obtain an 85% confidence interval for an unknown parameter. Approximately how many of those confidence intervals will contain the value of the unknown parameter? a) 136 b) 155 c) 100 d) 128

a) 136

A random sample is taken and the sample size is 30. The sample mean is 180 and the standard deviation is 11. Find a 95% confidence interval for the population mean. a) 175.89 to 184.11 b) 178.65 to 189.12 c) 185.46 to 190.21 d) 170.35 to 178.65

a) 175.89 to 184.11

The police have noted that they, on average, only need 2 police cars to patrol a 50-square-mile area in order to uphold the law, with a standard deviation of 1.25. Assume that the distribution is normal. What is the percentage chance that the police will require more than 3 police cars to monitor the area? a) 21% b) 15% c) 34% d) 7%

a) 21% Explanation: z = (data point - mean) / standard deviation z = (3 - 2)/1.25 = 0.8 The number from a z-score table for 0.8 is 0.7881. We want the numbers greater than this so we need to take 1 - 0.7881 = 0.2119 or about 21%

You have a fair coin and want to calculate the probability that if you flip the coin 20 times, you will get EXACTLY 14 heads. What is the probability for this event? a) 3.7% b) 14% c) 7% d) 5.6%

a) 3.7% Explanation: Binomial Distribution formula P(X = k) = (n/k) p^k (1-p)^n-k P(X=14)=(20 14)0.5^14(1−0.5)^20−14=38760(0.514)(0.56)=.0370

There are 8 runners in the finale of the World Olympics series 100-meter sprint. Assuming that the order of finishing is important and that ties between the sprinters are impossible, how many different arrangements of 1st, 2nd, and 3rd place finishers could there be? a) 336 b) 6720 c) 3 d) 56

a) 336 Explanation: Use the permutation formula: nPr = n! / (n - r)! n = 8 r = 3 8P3 = 8! / (8 - 3)! = 336

Tom is playing a game that has a probability of success, P, of 0.6. He plays 3 games (n = 3). Using the binomial probability formula, what is the probability that he will win 2 games (x =2)? a) 43.2% b) 17.28% c) 36.4% d) 72%

a) 43.2% Explanation Use the binomial probability formula and plug in the values: B(x; n, P) = nCx * P^x * (1 - P)^(n - x) B(x; n, P) = [3!/(1!2!)] * (0.6)^2 * (0.4)^1 = 0.432 = 43.2%

On a history exam, the average score was 75, with a standard deviation of 15. Assume that the distribution of the scores is normal. What percentage of the class scored between 60 and 80 points? a) 47% b) 39% c) 52% d) 71%

a) 47%

A survey of 250 college students found that 136 students had a part time job. Construct a 95% confidence interval for the percentage of college students who have a part time job. a) 48% to 61% b) 34% to 75% c) 42% to 54% d) 53% to 55%

a) 48% to 61% Explanation: n = 250 136/250 = 54.4% or 0.544 p(hat) = 0.544 q(hat) = 1 - 0.544 = 0.456 s sub p(hat) = √((0.544)(0.456)/250) = 0.0315 To find the z value: 1 - 0.95)/2 = 0.025 0.025 + 0.95 = 0.975 0.975 corresponds to a z value of 1.96 on the table Confidence interval: p(hat) ± z ∗ s sub p(hat) 0.544 ± 1.96(0.0315) = 0.4822 to 0.60574 This corresponds to around 48% to 61 %.

Construct a 99% confidence interval for the following data set. n = 1,500 q-hat = 0.48 a) 48.7% to 55.3% b) 53.6% to 62.4% c) 52.5% to 69.5% d) 49.7% to 57.9%

a) 48.7% to 55.3%

A researcher conducts a survey to know how many parents feel that sports are important for the development of children. He interviews 125 parents and 76 say that they feel that sports are important. Construct the 95% confidence interval for the population of parents who feel that sports are important for the development of children. a) 52.5% to 69.5% b) 53.6% to 62.4% c) 48.7% to 55.3% d) 49.7% to 57.9%

a) 52.5% to 69.5% Explanation: n = 125 x = 76 p = 76/125 = 0.61 q = 1 - p = 1 - 0.61 = 0.39 alpha = 1 - 0.95 = 0.05 z-value = 1.96 E = (1.96)(z-value sub alpha/2) (sqrt ((0.61*0.39)/ 125) = 0.0855 p + 0.0855 = 0.6955 p - 0.0855 = 0.5245

A store wants to know how many of its employees feel satisfied with their jobs. They conduct a survey with 300 employees and find that 185 of them are satisfied with their jobs. Construct a 95% confidence interval for the population of employees who are satisfied with their jobs. a) 56.5% to 67.5% b) 52.3% to 62.2% c) 54.8% to 61.4% d) 59.1% to 60.1%

a) 56.5% to 67.5%

Which of the following is an example of interval data? a) 7 people in the class are between 5 feet 7 inches and 5 feet 9 inches, 11 are between 5 feet 9 inches and 6 foot 2 inches and 6 people are between 6 feet 2 inches and 6 feet 5 inches. b) If the number of people in your class compared to the largest class in the school have a ratio of 24:32, which can be simplified to 3:4 if you divide it by eight. c) If most of your classmates like the color blue, while only 1 person likes green and the rest of your class likes red. d) 4 people in your class won medals in the school championship. Of those four, two people were first in sprinting, one was the second in jumping, while one won third place in acrobatic rock and roll.

a) 7 people in the class are between 5 feet 7 inches and 5 feet 9 inches, 11 are between 5 feet 9 inches and 6 foot 2 inches and 6 people are between 6 feet 2 inches and 6 feet 5 inches.

The mean score of a medical test is 72.21 with a standard deviation of 2.5. Find a 95% confidence interval for a random sample of 25 students with the following scores. a) 71.18 to 73.24 b) 72.25 to 72.30 c) 70.12 to 75.12 d) 73.45 to 74.65

a) 71.18 to 73.24

A random sample is taken and the sample size is 25. The sample is normally distributed, the sample mean is 89, and the standard deviation is 5.5. Find a 90% confidence interval for the population mean. a) 87.12 to 90.88 b) 78.69 to 98.34 c) 88.21 to 97.54 d) 88.56 to 89.16

a) 87.12 to 90.88 Explanation: s = 5.5 n = 25 df = n - 1 = 24 x-bar = sample mean = 89 s(x-bar) = s / √n = 5.5 / √25 = 1.1 confidence level = 0.90 To find t 1 - 0.90 = 0.10 0.10 divided by 2 = 0.05 From the t-distribution table for df = 24 and 0.05, t = 1.71 Confidence interval = x-bar ± t ∗ s(x-bar) = 89 ± (1.71 ∗ 1.1) 89 - 1.881 and 89 + 1.881 87.12 and 90.88

Suppose that you take 500 simple random samples from a population and that, for each sample, you obtain a confidence interval for an unknown parameter. You expect 475 of the confidence intervals to actually contain the value of the unknown parameter. What was the confidence interval you calculated? a) 95% b) 90% c) 85% d) 80%

a) 95%

Which of the following scenarios exemplifies a process that would be described by a continuous random variable? a) A group of statistics students measures the height distribution of the population of Seattle, Washington. b) A football referee flips a coin at the beginning of the game to determine which team will have the choice to kick or receive. c) A gambler in a casino bets on red while playing roulette. d) Census workers are counting the population of the city of Seattle, Washington.

a) A group of statistics students measures the height distribution of the population of Seattle, Washington.

Which of the following best defines inferential statistics? a) Analyzing a sample to make general conclusions about a population b) Creating graphical representation of data, such as charts c) Calculating the data and understanding its traits, such as by calculating means and averages d) Establishing whether there is a strong correlation between two events relevant to the study

a) Analyzing a sample to make general conclusions about a population

What is the expected value of 79 customers purchasing a spoon tie if the success probability is 35%? a) Approximately 28 customers b) Approximately 35 customers c) Approximately 25 customers d) Approximately 39 customers

a) Approximately 28 customers 79 * 0.35 = 27.65 = Approximately 28

Tom is playing a game of craps and and if the sum is 7 or 11, then he wins. If the sum is 2, 3 or 12, then he loses. If the sum is anything else, then he/she continues throwing until that number appears again, or he throws a 7, where the game ends in a loss. What would a binomial distribution of the data allow us to do? a) Calculate the probability of what each toss will do. b) Create a continuous data pattern. c) Use regression results to understand the data. d) Use correlation to help us understand the data.

a) Calculate the probability of what each toss will do. P = 6/36 = 1/6

Which of the following is NOT a method that can be used to determine whether you should accept or reject the null hypothesis? a) Correlation method b) P-value method c) Region of acceptance method d) All of the answers are correct.

a) Correlation method

Thomas, a worker at Goldman Sachs, has calculated that for each dollar they invest into a low rated bond, the impact on their revenue can be explained with the equation y=-1.03x + 0.8. What is the best interpretation of the slope of this regression equation? a) For every dollar they invest into a low rated bond, they are likely to lose 1.03 dollars b) For every dollar they invest into a low rated bond, they are likely to lose 0.33 dollars c) For every dollar they invest into a low rated bond, they are likely to lose 0.8 dollars d) For every dollar they invest into a low rated bond, they are likely to gain 1.83 dollars

a) For every dollar they invest into a low rated bond, they are likely to lose 1.03 dollars

A soccer coach wants to know how many hours per week his players spend training at home. He has 20 players and he decides to ask the first 4 players to arrive at the Monday's soccer practice how many hours they spend training per week. He then calculated that they spend an average of 10 hours per week. Therefore, he assumed that all the players train 10 hours per week. Is this an example of a simple random sample? a) No, because each student did not have an equal chance of being selected. b) Yes, because each student had an equal chance of being selected. c) No, because he didn't sample every soccer player. d) Yes, the minimum number of students sampled needs to be four for it to be a simple random sample.

a) No, because each student did not have an equal chance of being selected.

Sara and Tamara are having an argument because Sara, who has blue eyes, claims that 2 people out of a hundred have blue eyes, while Tamara thinks it is far more common. To test their ideas, they have conducted an experiment in their city which has 100,000 people, by determining the eye color on 2,500 people they find on the streets. Which of the following is correct regarding their experiment? a) Sara's hypothesis is that 2% of the people have blue eyes. b) The sample of their experiment is 100,000. c) The entire population of the experiment is all of the people who live in the country, rather than that in the city. d) All the answers are correct.

a) Sara's hypothesis is that 2% of the people have blue eyes.

Two regular dice are rolled. For which of the following is the probability 1:12? a) That the two dice will have a sum equal to 4 b) That if the first dice is a 6, the second will also be 6 c) That if the first dice is a 6, the second will be a 4 d) That the two dice will have a sum equal to 6

a) That the two dice will have a sum equal to 4 Explanation: The best way to answer this question is to find the probability of each answer possibility. The one that gives a probability of 1:12 is that the two dice will have a sum equal to 4. There are three possibilities for this: 1 + 3, 3 + 1, and 2 + 2. (You only need to list 2 + 2 once.) Since there are 2 dice and each has 6 sides there are 36 total possible outcomes. 3:36 simplifies to 1:12.

Joseph asks 20 people in his math class if they are comfortable with using technology. Seven out of the 20 say they are comfortable with using technology. Calculate the theoretical and the actual probability of this scenario. a) Theoretical: 50% Actual: 35% b) Theoretical: 70% Actual: 50% c) Theoretical: 35% Actual: 50% d) Theoretical: 50% Actual: 70%

a) Theoretical: 50% Actual: 35%

Thomson Global is a PR company that focuses on online promotion. They are interested in knowing if the mean number of views on their website differs between frequent internet users and inexperienced users. Which method of analysis would be most appropriate? a) Two-tailed paired t-test b) Multivariate hypothesis test c) Systemic qualitative analysis d) Literature review

a) Two-tailed paired t-test

When would you use the t-distribution procedure to find the confidence interval for the population mean? a) When you do not know the standard deviation of a normally distributed population. b) Only when you have the standard deviation and mean of a normally distributed population. c) When you are working a population that does not have a normal distribution. d) When the only thing that you know about a population is its size.

a) When you do not know the standard deviation of a normally distributed population.

Suppose you play a game where you roll a set of 2 fair dice. If you roll a 4, 5, or 6, you will lose $6, but if you roll anything else, then you win $3. How much money will you gain or lose per each throwing? a) You will average exactly 0 per each throwing of the dice. b) You will average $0.25 per each throwing of the dice. c) You will lose exactly $1 per each throwing of the dice. d) You will lose $0.5 per each throwing of the dice.

a) You will average exactly 0 per each throwing of the dice.

Sarah took a random sample for her research project and she wants to use a t-test as a hypothesis test. In order to do so, the population must be _____ with a(n) _____ standard deviation. a) normally distributed, unknown b) larger than 100, known c) smaller than 100, unknown d) normally distributed, known

a) normally distributed, unknown

If you are worried about global warming and you measure the temperature in June each year, the data you measure is _____. a) quantitative b) qualitative c) categorical d) discrete

a) quantitative

The _____ is a measure of distance from the mean in terms of how many standard deviations it is removed from the mean. a) z-score b) variance c) spread d) normal distribution

a) z-score

Mathew is a math teacher who has recently conducted an exam in his class. The mean score result is 62, while the standard deviation was 20. Assume that the scores are normally distributed. If a student scored 42 points, what was his z score? a) 1 b) -1 c) 5.2 d) 20

b) -1

If z = 2 and -2, what area falls OUTSIDE these z values on a standard normal curve? a) 0.024 b) 0.046 c) 0.081 d) 0.00012

b) 0.046 Explanation: The area between z values of 2 and -2 is 2(0.4772) or 0.9544. To find the area outside of this we must subtract this number from 1. 1 - 0.9544 = 0.0456 which rounds to 0.046.

What is the value of alpha for a 90% confidence interval? a) 0.01 b) 0.10 c) 0.05 d) 0.25

b) 0.10

In a game of blackjack where you are the only player, the first card you draw is the king and the second is an eight. You decide to draw another card. What is the probability that upon drawing another card, you will lose (go over 21)? Assume that aces can count as 1 and you are playing with a standard 52 card deck. a) 16% b) 76% c) 24% d) 7%

b) 76% Explanation: Since you have already drawn 2 cards, there are 50 cards left. Of those 50 cards, 12 will give a total of 21 or less (4 aces, 4 2s, 4 3s). So, 38 cards will give a total over 21 (50 - 12 = 38). The probability of going over 21 is 38/50 or 76%.

A package of sweet food has 10 cookies, 10 cakes, 10 waffles and 10 small pieces of candy. You have randomly taken food from the package and retrieved a cookie. Without returning the cookie you have again tried to take something from the package. What is the probability you will once again retrieve a cookie? a) 1/4 b) 9/39 c) 0.0576 d) 0.333

b) 9/39

Mark, a teacher, asks his students what they all like most about the school. He then groups the data in order to understand what their preferences are. Why is this an example of categorical data? a) Because it provides a numerical result b) Because it provides preference that can be collected in groups or topics c) Because it provides us with a result which can be used to understand the relationship between various variables d) Because the result can in no way be subject to statistical analysis

b) Because it provides preference that can be collected in groups or topics

What is the number of successes in a binomial experiment called? a) Expected Value b) Binomial Random Variable c) Standard Deviation d) Variance

b) Binomial Random Variable

Which of the following assigns probabilities to the potential values of the variable x? a) Binomial distribution b) Binomial formula c) Categorical distribution d) Continuous probability distribution

b) Binomial formula

Which of the following is an example of descriptive statistics? a) Based on a sample of 100 responses, a researcher calculating how an entire population is going to vote b) Calculating the mean and median for the revenue of a marketing company c) Analyzing two sets of data and noticing that they tend to move in the same direction, so you calculate the regression equation for this data d) Based on 1000 responses to your poll, predicting how 10,000 people will likely respond

b) Calculating the mean and median for the revenue of a marketing company

You're drawing a card from a standard deck with 52 cards. For which of the following is your probability of drawing this card 2:13? a) It's the probability of drawing a king. b) It's the probability of drawing a jack or a ten. c) It's the probability of drawing a jack, ten or a queen. d) It's the probability of drawing a jack, ten, a queen or a king.

b) It's the probability of drawing a jack or a ten.

Tamara is a math teacher in high school. She has noticed that her recent exam results have a normal distribution. What portion of the exam results will NOT be included within two standard deviations of the mean? a) Less than 95% b) Less than 5% c) Greater than 68% d) Greater than 32%

b) Less than 5%

A researcher is conducting a test and the resulting P-value is 0.023. The significance level of the test is 5%. What should the researcher do? a) Accept the null hypothesis because the P-value is less than the significance level. b) Reject the null hypothesis because the P-value is less than the significance level. c) Reject the alternative hypothesis because the P-value is less than the significance level. d) Repeat the test because the P-value should not be less than 0.05.

b) Reject the null hypothesis because the P-value is less than the significance level.

Three coins are tossed. For which of the following is the probability 7/8? a) That there will be only one head b) That there will be at least one tails c) That at least two of them will be tails d) That there will be exactly one head and one tails

b) That there will be at least one tails

You're rolling a 20-sided die where each side shows a number from 1-20. For which of the following is it probable that the probability will be 1:4? a) That you will roll a 2 b) That you will roll two consecutive odd numbers c) That you will roll three consecutive odd numbers d) That you will roll two dice and the result will be 4

b) That you will roll two consecutive odd numbers

Independent outcomes, only two possible outcomes and a fixed number of trials are all assumptions of a _____. a) regression model b) binomial probability function c) normal distribution d) continuous probability function

b) binomial probability function

A tobacco company is trying to increase its appeal to young working class people. They have randomly taken 100 participants from that age group and are asking how they should market their products. The number of young working class people is _____. a) qualitative and discrete b) quantitative and discrete c) categorical and continuous d) categorical and discrete

b) quantitative and discrete

If the P-value is 0.049 and the significance level is 0.05, then we _____. a) confirm the null hypothesis b) reject the null hypothesis c) repeat the test, as it is inconclusive d) have to think of a new null hypothesis

b) reject the null hypothesis

Your manager is asking you to measure the relationship between the amount of money spent on advertisement (x) and the number of products consumers buy (y). Based on the following data and by calculating the regression equation, how much money do you need to spend to sell 20 products? (6,1)(14,3)(22,5)(34,8)(50,12) a) $76 b) $80 c) $82 d) $160

c) $82 Explanation: y = 0.25x - 0.5

The Davis Cup tennis coach has 4 players and is trying to decide which two he is going to send to play the crucial doubles match. The coach is going to announce the top 2 players in order and they will play the match. In how many different ways could the coach choose and order his players? a) 8 b) 2 c) 12 d) 16

c) 12

The probability distribution for x is presented in the following table. What is the expected value of the random variable x? (x, P) (2, 0.4) (3, 0.1) (4, 0.5) a) 1.1 b) 2.1 c) 3.1 d) 3.6

c) 3.1

The probability distribution for x is presented in the following table. What is the expected value of the random variable x? (x,P)(2, 0.4) (3, 0.1) (4, 0.5) a) 1.1 b) 2.1 c) 3.1 d) 3.6

c) 3.1

What is game theory? a) A theory on how many hours teenagers spend on games b) A theory on how gaming works c) A field of math used to guide logical decision making d) The expectation of what will happen in any given event

c) A field of math used to guide logical decision making

A young teaching assistant is helping out with some work at a local institute. His superiors are very surprised that he made several very bad mistakes. The size of his sample wasn't representative and he set the significance level too high, which lead him to accept the null hypothesis, although it was obviously false. Which of the above scenarios is a type II error? a) Having a non-representative sample b) Setting the significance level wrong c) Accepting a false null hypothesis d) All of the answers are correct.

c) Accepting a false null hypothesis

Tom is playing a game of craps and if the sum is 7 or 11, then he wins. If the sum is 2, 3 or 12, then he loses. If the sum is anything else, then he continues throwing until that number appears again or he throws a 7, where the game ends in a loss. If the probability of Tom winning is 0.4929, why is it not profitable for him to play the game over the long-term? a) Because his odds of winning on the first try are only 1/36. b) Because his odds of winning on the second try are 6/256. c) Because his probability of winning is lower than 50%. d) Because he will throw 11 too often.

c) Because his probability of winning is lower than 50%.

Which of the following uses a sample statistic? a) Confidence interval b) Parameter c) Both of these are correct. d) Neither of these is correct.

c) Both of these are correct.

You are pulling cards from a standard 52-card deck. For which of the following is the probability 12 / 2652? (You do not replace the card pulled.) a) Drawing a king and a queen b) Drawing an ace, a king and then another king c) Drawing two consecutive kings d) Drawing a jack

c) Drawing two consecutive kings Explanation: Probability of the first king: 4/52 Probability of the second king: 3/51 4/52 ∗ 3/51 = 12/2652

Which of the following is FALSE regarding the binomial probability distribution? a) It is a mathematical construct that is used to model the probability of observing r successes in n trials. b) It is the most often used discrete probability distribution in statistics. c) It is calculated based on a formula where p is the significance level for a single event and q is the quantity of data present. d) None of the answers are correct.

c) It is calculated based on a formula where p is the significance level for a single event and q is the quantity of data present.

Which of the following is an example of a type I error? a) When the researcher uses a wrong research method. b) When the researcher sets the null hypothesis incorrectly. c) When the researcher gets a result which suggests the null hypothesis is false, but it is actually correct. d) When the researcher gets a result which suggests the null hypothesis is correct, but it is actually false.

c) When the researcher gets a result which suggests the null hypothesis is false, but it is actually correct.

A worker has noticed that the more time he spends at work (x), the less money he is likely to make (y) in conducting transactions for his firm. Which of the following regression equations MOST suggests such a possibility? a) y=13x+0.1 b) y=0.02x+0.5 c) y=-3x+4 d) y=x-0.3

c) y=-3x+4

What is a probability formula that uses factorials to find the number of possible combinations of all the outcomes in the experiment? combination formula correlation formula co-efficient formula permutation formula

combination formula

A news station has planned to invest $50,000 this year in advertising and plans to decrease the amount they spend in advertising by $5,000 each year for the next 10 years. If x represents the number of years passed and y the value of their investment in advertising, how much will they spend on advertising at two years? (Using this information, write a linear equation and substitute in the number of years to find the answer.) a) $45,000 b) $95,000 c) $50,000 d) $40,000

d) $40,000

Thomson Industries needs to maintain its average quarterly revenue to be at least $150,000 or else the interest rates on their loans will go up. If their revenue is as displayed in the following table, what is the LEAST that they have to make in the fourth quarter in order to avoid the higher interest rates? a) 160,000 b) 155,000 c) 200,500 d) 216,000

d) 216,000

Which of the following data sets has a median as a more representative central figure than the mean? a) 2, 4, 6, 8, 10, 12, 14 b) 1, 6, 9, 12, 15, 18, 21, 23 c) 1000, 1200, 800, 1200, 1000, 1400 d) 30, 99, 1, 28, 26, 31, 28

d) 30, 99, 1, 28, 26, 31, 28

C is the result of the intersect of A and B. If C= {1,3,6}, which of the following are A and B? a) A = {1,3,4,5,6} and B = {-1,-2,-3,-4} b) A = {1,3} and B = {6} c) A = {1,3,7,8,10} and B = {1,3,6} d) A = {1,2,3,6,8} and B = {0,1,3,6,9}

d) A = {1,2,3,6,8} and B = {0,1,3,6,9}

Which of the following statements is TRUE in regards to a binomial experiment? a) In a binomial experiment, the outcome of one trial must not have any influence over the other. b) In a binomial experiment, success or failure are the only two possible outcomes. c) A binomial experiment consist of a fixed number of trials. d) All choices are true.

d) All choices are true.

Which of the following is an example of the use of inferential statistics? a) A company spends $15,000 in advertisement, while its total revenue is $300,000, which means it spends 5% of its revenue on advertisement. b) If a poll shows that it is likely that 35 of the 100 people want to buy a car, then 35% of the people that were asked stated they will likely buy a car. c) If you need to understand a legal document and understand how a decision there may be set as a precedent. d) If a company performs a poll on a random number of families and then uses their responses to predict how all of the other families in the country will behave.

d) If a company performs a poll on a random number of families and then uses their responses to predict how all of the other families in the country will behave.

Identify in which of the following it would be MOST useful to use the z statistic rather than the t statistic: a) If you have a sample of 2 measurements b) If you have a sample of 20 measurements c) If you have a sample of 400 measurements d) If you have a sample of 4000 measurements

d) If you have a sample of 4000 measurements

A researcher is conducting a hypothesis test. Which of the following P-values would MOST suggest he should reject the null hypothesis? a) P=0.90 b) P=0.11 c) P=0.52 d) P=0.06

d) P=0.06

Two companies, AMR and TDA, focus on selling luxurious boats and have provided how many they have sold each month. Perform a paired t-test and interpret the P-value: a) It is significant at the 0.01 level of significance. b) It is significant at the 0.05 level of significance. c) It is significant at the 0.1 level of significance. d) The P-value is larger than 0.1.

d) The P-value is larger than 0.1.

Which of the following is NOT an example of descriptive data? a) A graphical representation of data, such as various bar graphs and pie graphs b) Averages c) Means and medians d) Using samples to predict how the entire population will respond

d) Using samples to predict how the entire population will respond

Identify which of the following distributions has the largest spread: a) When the mean is 14 and the standard deviation is 0.5. b) When the mean is 7 and the standard deviation is 3. c) When the mean is 30 and the standard deviation is 1. d) When the mean is 11 and the standard deviation is 4.

d) When the mean is 11 and the standard deviation is 4.

Identify in which of the following should we reject the null hypothesis: a) When the result of the P-value is 0.5 at a significance level of 0.05 b) When the result of the P-value is 0.05 at a significance level of 0.01 c) When the result of the P-value is 0.99 at a significance level of 0.01 d) When the result of the P-value is 0.025 at a significance level of 0.05

d) When the result of the P-value is 0.025 at a significance level of 0.05

Bar charts are best used to represent _____ data. a) qualitative b) discrete c) continuous d) categorical

d) categorical

A newspaper agency called 100 people and recorded their responses on how they will vote in the election. Based on their responses, they calculated that the Democratic Party has a 55% chance of winning the election. This is an example of the use of _____. descriptive statistics concluding statistics inferential statistics causation statistics

inferential statistics

Given: Mean, Standard deviation, confidence interval and sample size

mean (+/-) confidence interval (s/(sqrt n))

The name of the company you work for is an example of _____ data. nominal ordinal interval quantitative

nominal

In a school math competition, the order of winners is an example of _____ data. nominal ordinal interval ratio

ordinal

Which of the following r values suggests a moderate negative relationship? r=0.32 r=0 r=-0.44 r=-0.99

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