Ap Stats First Semester Final Exam

26. Create a modified box-and-whisker plot for each of the three data sets. Then use the plot and the values of the five-number summary to answer the following question: Which team has the greatest variation in the points per game for the middle 50% of their observations?

Boston

39. Assume that normal curve A and normal curve B have identical population means. Assume further that A has a greater population standard deviation than B. Which curve is taller, and why?

Curve B is taller because smaller standard deviations produce thinner curves.

What are the categorical variables in your survey?

Everything but average annual income and family size

43. In population W, what is the probability that a randomly selected subject will weigh between 140 and 180 pounds?

0.576

Here are some data on the average hours spent studying per day by a sample group of college students. Average Hours of Study Frequency 0 - 2 45 3 - 4 35 5 - 6 29 7 - 10 21 The cumulative relative frequency of students who study 4 hours or fewer a day is:

0.615

Consider a complete table of relative frequencies. The sum of the relative frequency column in such a table must be:

1

20. Since the distribution of housing prices in a community is usually skewed right, which measure of center should you use for housing pric

6.125

Consider these eight observations: {11,6,2,5,8,4,4,9}. What is the mean?

6.125

53. Find the GRE score at the upper quartile, Q3.

613

What area, to the nearest whole percent, of the normal curve is located between z = -0.6 and z = 1.4?

64%

47. To the nearest whole number, what percentile is associated with z = 1.2?

88th percentile

55. Consider a normal distribution with µ = 65 and σ = 4. A sample of size 950 is drawn from this population. Approximately how many of the 950 cases would you expect to find between 57 and 73?

903

A symmetric distribution can't have which of the following characteristics?

A long tail on one side

33. Why is the IQR considered to be a resistant statistic?

Adding a new extreme observation has little effect on it.

63. A normal curve table tells you that the probability lying below z = -1 is 0.1587. This can be interpreted as:

All of the above

Which league has the team that had hit the most home runs by midseason, and how many home runs had that team hit? Which league had the team with the fewest home runs?

American, 149, American

64. You have two normally distributed populations: Population A:Mean = 50 Standard deviation = 12 Population B:Mean = 75 Standard deviation = 15 The area under the normal curve is greatest in which scenario?

Area above 80 in Population B

59. The proper notation for a normal distribution with a mean of 250 and standard deviation of 25 is

N(250, 25)

62. When you have a normal distribution and you know that the area above a given value of x is 0.35, you also know that:

None of the above.

You want to know something about your neighbors, so you give them a survey. The survey collects the following data about each family on your block: family size, the kind of pets they have, the grade of the youngest child in the family, the family's average annual income over the last five years, what the dad does for a living, whether the mom works, and their phone number. Each kind of data you collect about a family is a variable. Which of the variables you collect are continuous data?

Only average annual income

1. Which one of the following activities is not an example of data gathering?

Reaching a conclusion about the results of a reading program

2. Which of these are categorical data?

The different types of anteaters

34. Which measure of central tendency and measure of variation should be used with a normally distributed distri

The mean and standard deviation

Six radio listeners are surveyed. Their favorite FM stations are: 89.1, 89.1 89.1, 94.7, 94.7 and 104.3. Based on these data, you want to name the favorite station of a typical listener. You should name:

The mode, which is 89.1

Which of the following would most likely be graphed as a bar chart rather than a histogram?

The number of blue, red, black, and white cars in a random sample of 500 cars B. The number of students in a mid-size university who own Macintosh or PC computers C. The ethnic distribution for a major city D. The number of people in various management positions at a large electronics store E. All of the above

16. True or False: If the population of interest is all day care centers in the United States, a sample of day care centers could be either all day care centers in New York City or a randomly selected group of day care centers throughout the US. Either sample is equally good.

false

56. A normal probability plot:

graphs raw scores against z-scores of percentile ranks

The kind of sampling strategy least likely to produce statistics that are good estimates of population parameters is a:

haphazard sample

All the following statements about the sample standard deviation are true, except:

the standard deviation is negative when there are extreme values in the sample.

5. True or False: In the survey of your neighbors described above, the only discrete quantitative data you're collecting about your neighbors is family size.

true

True or False: The number of home runs made by most National League teams were in the 90s; the number of home runs made by most teams overall were in the 80s.

true

61. In a normal distribution with a mean of 30 and a standard deviation of 5, you'd find the largest proportion of cases between:

x = 35 and x = 50

Population H is a group of women with normally distributed heights. Population H has a population mean of 66 inches and a population standard deviation of 2.5 inches. In population H, what is the z-score, to the nearest tenth, associated with the height 65 inches?

z = -0.4

You measured the weights of members of population W and found the weights to be normally distributed. The distribution has a population mean weight of 160 pounds and a population standard deviation of 25 pounds. 41. For population W, find the z-score associated with a weight of 120 pounds.

z = -1.6

42. For population W, what is the percentile for the weight 160 pounds?

50th percentil

54. Find the z-score for the lower quartile of any normal curve. Round your answer to the nearest hundredth.

-0.67

Here are some data on the average hours spent studying per day by a sample group of college students. Average Hours of Study Frequency 0 - 2 45 3 - 4 35 5 - 6 29 7 - 10 21 9. The relative frequency of students who study 5 - 6 hours a day is:

0.223

Estimate the relative frequency of countries with 20 - 22 days of no rainfall in the month of January.

0.32

66. Calculate the residual for a block with 10 streetlights and 1 crime a month. A. -0.6

1.7

14. How many fewer home runs did the team with the fewest home runs in the American League have than the team with the fewest home runs in the National League? How many more home runs did the team with the highest home runs in the American League have than the highest team in the National League?

14, 33

38. Give, in millimeters, a minimum and a maximum thickness that will include 95% of the population of bolts.

19.98 to 20.02 millimeters

37. Give, in millimeters, a minimum and maximum thickness that includes 68% of the population of bolts.

19.99 to 20.01 millimeters

31. What is the interquartile range for the data in the table?

25.5

32. Based on the data in the table, what is the largest number of births in a month you could possibly have and still have a lower outlier?

255

To the nearest whole number, what percentile is associated with z = -0.68?

25th percentile

30. What is the lower quartile for the data in the table?

294

27. The following hypothetical data set shows the purchase price (in thousands) for a sample of 3-bedroom, 2-bathroom homes in Essex County, MA over the past year. Compute the five-number summary and create a modified box plot. How many outliers are present in this distribution? 250, 254, 320, 342, 221, 235, 210, 426, 210, 298, 231, 254, 278, 234, 236, 235, 300, 401, 129, 234, 235, 235, 245

3

28. What is the median for the data in the table?

306.5

29. What is the upper quartile for the data in the table?

319.5

Calculate, to the nearest whole number, the sample standard deviation of this data set, which is a sample from a larger population: {71, 75, 65, 73, 69, 77, and 67}.

4

40. Using the empirical rule, you can assume that what percent of the normal distribution is outside two standard deviations of the mean in both directions?

5%

Consider these eight observations: {11,6,2,5,8,4,4,9}. What is the median?

5.5

67. Using the regression equation above, correctly interpret the slope.

For every additional streetlight per block, the crimes per month decrease by 0.2.

Histograms are most useful in displaying:

Large numeric data sets