Chapter 2 Quiz

A survey of radio stations was conducted following the attacks on the World Trade Center in 20012001 . One of the variables recorded was the region in which the station was located (east, center, or west). In addition to the variable "region," the following information was collected: the quartile of the media market (top, second, third, and fourth), state, rank (a number between 11 and 205205 ), and share (a number between 00 and 77 ). The modified boxplot of station ranks above identifies how many outliers? 0 3 2 1

0

In my friend's coin purse, I found 12 pennies. The ages, in years, of the pennies obtained by subtracting the year stamped on the coin from 2016 follow. 22, 14, 8, 1, 9, 0, 31, 2, 13, 3, 11, 10 Rounding to the nearest tenth, the mean and median of this distribution (in years) are: 10.3 and 9.5. 10.3 and 10.5. 11.3 and 9.5. 9.5 and 10.3.

10.3 and 9.5

A sample was taken of the salaries of four employees from a large company. The following are their salaries, in thousands of dollars, for this year. 33 31 24 36 The variance of their salaries is: 26 5.1. 31

26

A violin student records the number of hours she spends practicing during each of nine consecutive weeks: 6.2 5.0 4.3 7.4 5.8 7.2 8.4 1.2 6.3 What is the median number of hours spent practicing per week during this period? 5.76 hours 8.40 hours 6.15 hours 6.20 hours

6.20 hours

A survey of radio stations was conducted following the attacks on the World Trade Center in 20012001 . One of the variables recorded was the region in which the station was located (east, center, or west). In addition to the variable "region," the following information was collected: the quartile of the media market (top, second, third, and fourth), state, rank (a number between 11 and 205205 ), and share (a number between 00 and 77 ). The side-by-side boxplots of station rank, above, show: different median ranks between the regions. more variability in ranks of coast stations. similar minimum ranks between regions. All of the answer options are correct.

All of the answer options are correct

Why might someone decide to use a boxplot to represent a set of data rather than a histogram? Boxplots clearly illustrate the mean. Boxplots illustrate a skew more clearly. Boxplots are better for side by side comparisons

Boxplots are better for side‑by‑side comparisons.

Which of the following measures is generally most resistant to outliers? the mean the 𝐼𝑄𝑅 the standard deviation

IQR

The following histogram represents the distribution of acceptance rates (percent accepted) among 20 top business school MBA programs in 2015. In each class interval, the left endpoint is included but not the right. Which statement is true? The first quartile must be at least 17.5 but less than 22.5. Neither choice is true. The median rate must be less than 25.

The first quartile must be at least 17.5 but less than 22.5.

The histogram shows the distribution of the annual hours of commuting delay per traveler for 46 small and medium urban areas, fewer than one million in population. Which of the following must be true? The mean is the same as the median. The mean is less than the median. The mean is greater than the median.

The mean is greater than the median

Does the value of the standard deviation depend on the value of the mean? Yes, because the mean must be known in order to calculate the standard deviation. Yes, because if the mean gets larger, the standard deviation will also get larger. No, because the center of a distribution and the spread are not related.

Yes, because the mean must be known in order to calculate the standard deviation.

A disadvantage of using a boxplot rather than a histogram is: a boxplot shows the mean as the measure of center. a boxplot does not illustrate variability. a boxplot shows less detail.

a boxplot shows less detail.

The histogram shows the distribution of the annual hours of commuting delay per traveler for 46 small and medium urban areas, fewer than one million in population. Which measure of center and variability would be most appropriate to report for this distribution? mean and quartiles median and quartiles mean and standard deviation median and standard deviation

median and quartiles

You receive faxes with six bids (in millions of dollars): 2.2, 1.3, 1.9, 1.2, 2.4, and x, where 𝑥 is some number that is too blurry to read. Without knowing what x is, you know that the median: could be any number between 1.2 and 2.4. must be at least 1.3 and no more than 2.2. must be 1.9.

must be at least 1.3 and no more than 2.2

The five‑number summary of the scores on a test, in increasing order from the minimum to the maximum, is: 35 60 65 70 90 Based on this information: there are low suspected outliers, but not high suspected outliers. there are both high and low suspected outliers. there are no suspected outliers. there are high suspected outliers, but not low suspected outliers.

there are both high and low suspected outliers.

Consumer Reports often reviews current‑model‑year cars. The boxplots given can help us compare the 0 to 60 miles per hour acceleration times (in seconds) of cars in several categories: small (4‑cylinder engines), family, large, upscale (6‑cylinder engines), and luxury (a mixture of 6‑ and 8‑cylinder engines). The smaller the acceleration time, the faster the car accelerates. In which category was the car with the fastest acceleration, that is, with the shortest acceleration time? luxury upscale large small

upscale