Statistics R Final Exam Review

Name: ______Date: ______Block:______

1. A ______is a characteristic or attribute of a subject that can assume different values? A) datum B) variable C) exponent D) sample

2. What level of measurement classifies data into mutually exclusive categories in which no order or ranking can be imposed on the data? A) nominal B) ordinal C) interval D) ratio

3. Classifying the fruit in a basket as apple, orange, or banana, is an example of the ______level of measurement? A) nominal B) ordinal C) interval D) ratio

4. If you were told that four students from a class of twenty were questioned for a poll about study habits, this would be an example of ______. A) random sampling B) systematic sampling C) stratified sampling D) cluster sampling 5. An independent variable can also be called a(n) A) free variable. B) explanatory variable. C) suggestive variable. D) outcome variable.

6. In a true experimental study, the subjects should be assigned to groups randomly. If this is not possible and a researcher uses intact groups, they are performing a ______. A) quasi-experimental study B) convoluted study C) observational study D) dependent study

7. In an advertisement for a car, a driver is shown driving expertly through a difficult road course. At the bottom of the ad, the following is included in small print "Professional driver on a closed course". Which of the following choices best describes this misuse of data? A) changing the subject B) detached statistics C) faulty survey questions D) implied connections

8. What are the boundaries of the class 12-18? A) 11.5 and 18.5 B) 9 and 21 C) 12 and 18 D) 6 9. In an ungrouped frequency distribution of the average age of high school graduates, what would be the boundaries for the class of graduates who were reported to be 18 years old? A) 17–19 years old B) 17.5 – 18.5 years old C) 17.6 – 18.5 years old D) 17.6 - 19.5 years old

10. Which of the following could be an ogive? 11. Karen is constructing a pie graph to represent the number of hours her classmates do homework each day. She found that 8 of 24 classmates did homework for three hours each day. In her pie graph, this would represent how many degrees? A) 135° B) 45° C) 120° D) 240°

12. Daniel Wiseman, a scientist for Gres-Trans Corp., wants to determine if the flow rate of a particular material changes with different changes in temperature. The data is plotted in the figure below. What type of relationship exists between the flow rate and the change in temperature?

A) negative B) positive C) There is no relationship. D) curvilinear

13. What type of graph is the figure below? A) Pareto chart B) pictograph C) ogive D) pie graph 14. Which of the following is the properly rounded mean for the given data? 7, 8, 13, 9, 10, 11 A) 10 B) 9.7 C) 9.67 D) 9

15. What is the midrange of the following data set? 3, 9, 8, 10, 2, 10, 16, 16, 16 A) 9 B) 10 C) 3 D) 16

16. A random sample of weights (in carats) of sapphires in a jeweler's collection is shown. Find the mean of the sample. Class Boundaries Frequency 0.95-2.95 12 2.95-4.95 10 4.95-6.95 12 6.95-8.95 11 8.95-10.95 8

A) 10.60 B) 5.69 C) 5.59 D) 5.95 17. The average resident of Metro City produces 550 pounds of solid waste each year, and the standard deviation is approximately 80 pounds. Use Chebyshev's theorem to find the weight range that contains at least 75% of all residents' annual garbage weights. A) Between 470 and 630 pounds B) Between 230 and 870 pounds C) Between 310 and 790 pounds D) Between 390 and 710 pounds

18. The size of the box in a boxplot shows the ______of the data set. A) difference between the mean and the median B) variance C) skewness D) interquartile range

19. A distribution in which approximately 68% of the data values fall within one standard deviation of the mean behaves according to A) the empirical rule. B) a symmetrical distribution. C) a boxplot. D) differential statistics.

20. If a data set has 9 values and a standard deviation 7.4, then the variance is ______. A) 54.8 B) 2.5 C) 18.3 D) 22.2 21. If a sportscaster makes an educated guess as to how well a team will do this season, he is using what type of probability? A) classical probability B) conditional probability C) empirical probability D) subjective probability

22. At Wassamatta University, 45.3% of the student body are males. Choose one student at random. What is the probability that the student is female? A) 4.7% B) 50% C) 45.3% D) 54.7%

23. A probability experiment has two steps. There are two possible results for the first step, call them "A" and "B". If the result for the first step was "A", then there would be 4 possible results for the second step. If the result for the first step was "B", then there would be 13 possible results for the second step. How many possible outcomes are there for this experiment? A) 52 B) 8 C) 13 D) 17

24. A coin is tossed 6 times. Find the probability that all 6 tosses are tails. A) 1/6 B) 1/36 C) 1/12 D) 1/64 25. Below are listed the numbers of engineers in various fields by sex. Choose one engineer at random. Find P(electrical | male). Mechanical Electrical Biomedical Male 9,968 4,686 6,883 Female 3,820 1,180 5,494

A) 0.799 B) 0.218 C) 0.146 D) 0.112

26. When two events are independent, the probability of both occurring is: A) P(A and B) = P(A)  P(B) B) P(A and B) = P(A) + P(B) C) P(A and B) = 1 - (P(A) + P(B)) D) P(A and B) = 1 - P(A)  P(B)

27. There are 3 first grade children, 4 second grade children, and 6 third grade children in a room. When choosing two children, what is the conditional probability of choosing a second grade child, given that either a first or a third grade child was chosen first? A) 1\4 B) 1\3 C) 3\4 D) 4\13

28. FizzFizz soda comes in two varieties, regular and diet. If a researcher has 6 boxes of each, how many ways can he select 2 boxes of each for a quality control test? A) 225 B) 90 C) 119 D) 12 29. A group of 5 children are choosing colored pencils to draw a picture. Each child is allowed to select one color. The available colors are green, red, and blue. If the second child refuses to use red pencils and the third child refuses to use blue pencils, then how many ways are there for the children to choose pencils? Assume that there are 10 pencils available of each color, and different children are allowed to choose the same color. A) 108 B) 30 C) 243 D) 81

30. A student and a professor each choose a number between 1 and 8 (1 and 8 are both possible choices). What is the probability that the two choose the same number? A) 1/64 B) 1/32 C) 1/8 D) 1/4

31. The following distribution is not a probability distribution because

X -2 -1 0 1 2

P(X) 0.08 0.21 0.42 0.14 0.30

A) the values of the variable are negative. B) the probability values are not increasing. C) the probability values do not add to 1. D) the probability values are not discrete.

32. Which of the following variables are discrete? i. the depth of a submarine ii. the number of torpedoes on a submarine iii. the speed of the submarine A) ii B) i and iii C) i and ii D) i, ii, and iii

33. What is the standard deviation of the following probability distribution?

X 0 2 4 6 8 P(X) 0.02 0.05 0.35 0.25 0.15

A) 2.6 B) 4.7 C) 5.4 D) 3.9

34. The number of cartoons watched on Saturday mornings by students in Mrs. Kelly's first grade class is shown below.

Number of cartoons watched, X 0 1 2 3 4 5

Probability P(X) 0.15 0.20 0.30 0.10 0.20 0.05

What is the mean of the data? A) 1.37 B) 2.15 C) 1.89 D) 1.18

35. An insurance company issues a policy for a diamond ring worth $13,500 for an annual premium of $202.50. If the company figures the probability of the ring to be lost or damaged is 0.01, what is the company's expected profit? A) $135.00 B) $62.50 C) $130.00 D) $67.50

36. In a large bag of marbles, 35% of them are red. A child chooses 4 marbles from this bag. If the child chooses the marbles at random, what is the chance that the child gets exactly three red marbles? A) 0.111 B) 0.207 C) 0.311 D) 0.172

37. If a normal distribution has a mean of 20 and a standard deviation of 10, then A) the median is 20 and the mode is 20. B) the median is 10 and the mode is 30. C) the median is 30 and the mode is 10. D) the median is 20 and the mode is 30.

38. Find the area under the standard normal distribution curve between z = –2.05 and z = 2.0. A) 0.4938 B) 0.4798 C) 0.9596 D) 0.9876

39. The average gas mileage of a certain model car is 26.0 miles per gallon. If the gas mileages are normally distributed with a standard deviation of 0.15 miles per gallon, find the probability that a car has a gas mileage of between 25.8 and 26.2 miles per gallon. A) 0.818 B) 0.318 C) 0.878 D) 0.409

40. For a normal distribution with a mean of 3 and a standard deviation of 2, the value 6 has a z value of A) –1.5 B) 1.5 C) 2.5 D) 3.5

41. A random sample of magnesium concentrations (in parts per million, or ppm) in ground water from various locations follows. Estimate the mean concentration of magnesium in ppm with 90% confidence. Assume σ = 20 . 45 104 16 102 48 58 9 110 61 16 57 90 70 123 81 117 40 5 50 59 124 82 103 74 123 74 30 119 58 67 29 8 64 13 89 A) 59.6 < < 72.9 B) 60.7 < < 71.8 C) 65.3 < < 67.2 D) 62.8 < < 69.6

42. A food snack manufacturer samples 11 bags of pretzels off the assembly line and weighs their contents. If the sample mean is 13.2 oz. and the sample standard deviation is 0.60 oz., find the 95% confidence interval of the true mean. A) 13.0 < < 13.4 B) 11.9 < < 14.5 C) 10.5 < < 15.9 D) 12.8 < < 13.6