Exam 2: Describing Quantitative Distributions With Numbers

Researchers measured the length of the central retrix (R1), a flight-involved tail feather, in 21 female long-tailed finches. A boxplot of the length, in millimeters (mm), is given here: Based on this boxplot, to which value is the interquartile range closest?

A maze experiment uses 24 lab rats of various ages, as summarized here: Age (in months) Number of rats 2 4 3 6 4 6 5 4 7 3 9 1 What is the median rat age (in months) for this maze experiment?

A sample was taken of the metabolic rates of men participating in a study regarding diets. The following boxplot depicts these rates (measured in kilocalories per 24 hours). Which of the following statements would be true if each person in this data set increased his rate by 120 kilocalories per 24 hours?

Brown tree snakes are an invasive species causing huge environmental and financial damage in Guam. In June 2000, researchers captured 504 brown tree snakes on Guam's Andersen Air Force Base. On average, the snakes weighed 121 g, and their weights ranged from 23 to 663 g at capture. From this information, what can we conclude about the shape of the distribution of brown tree snake masses?

In a study of the function of pectoral fins in fish, a graduate student examined 7 fish with the following lengths (in centimeters, cm): 30 28 29 27 31 25 29 What is the first quartile for these data?

A sample of 20 endangered species was obtained and the length of time (in months) since being placed on the list was recorded for each species. The ordered data follow: 52, 54, 58, 59, 59, 60, 60, 63, 65, 66, 67, 68, 69, 73, 74, 77, 78, 79, 79, 98 What is the first quartile of the length of time (in months) since being placed on the list for these 20 species?

The following histogram shows the yearly number of unprovoked attacks by alligators on people in Florida over a 33-year period. What must be the median yearly counts of alligator attacks?

In a study of the function of pectoral fins in fish, a graduate student examined 7 fish with the following lengths (in centimeters, cm): 30 28 29 27 31 25 29 What is the variance of these 7 fish lengths?

Geckos are lizards with specialized toe pads that enable them to easily climb all sorts of surfaces. A research team examined the adhesive properties of 7 Tokay geckos. Following are the toe-pad areas (in square centimeters, cm²) for this sample: 5.6 4.9 6.0 5.1 5.5 5.1 7.5 Rounded to two decimal places, what is the mean toe-pad area in this sample of geckos?

A sample of 20 endangered species was obtained and the length of time (in months) since being placed on the list was recorded for each species. The ordered data follow: 52, 54, 58, 59, 59, 60, 60, 63, 65, 66, 67, 68, 69, 73, 74, 77, 78, 79, 79, 98 Which value would need to be exceeded for a data point to be considered an outlier when using the 1.5 × IQR rule?

The following dotplot shows the migraine intensity (on a scale of 1 to 10) for 29 adults suffering from recurring migraines. What is the five-number summary for this data set?

Here is the ordered data of body temperatures (in degrees Fahrenheit) for 65 healthy adult women: 96.4, 96.7, 96.8, 97.2, 97.2, 97.4, 97.6, 97.7, 97.7, 97.8, 97.8, 97.8, 97.9, 97.9, 97.9, 98.0, 98.0, 98.0, 98.0, 98.0, 98.1, 98.2, 98.2, 98.2, 98.2, 98.2, 98.2, 98.3, 98.3, 98.3, 98.4, 98.4, 98.4, 98.4, 98.4, 98.5, 98.6, 98.6, 98.6, 98.6, 98.7, 98.7, 98.7, 98.7, 98.7, 98.7, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.9, 99.0, 99.0, 99.1, 99.1, 99.2, 99.2, 99.3, 99.4, 99.9, 100.0, 100.8 What is the third quartile of body temperatures for this data set?

The following dotplot shows the migraine intensity (on a scale of 1 to 10) for 29 adults suffering from recurring migraines. What is the median migraine intensity in this sample?

In a study of the function of pectoral fins in fish, a graduate student examined 7 fish with the following lengths (in centimeters, cm): 30 28 29 27 31 25 29 What is median fish length?

Geckos are lizards with specialized toe pads that enable them to easily climb all sorts of surfaces. A research team examined the adhesive properties of 7 Tokay geckos. Following are the toe-pad areas (in square centimeters, cm²) for this sample: 5.6 4.9 6.0 5.1 5.5 5.1 7.5 What is the value of the interquartile range for these data?

A study of freely forming groups in bars throughout Europe examined the number of individuals found in groups that were laughing together. A summary of the 501 groups examined is shown here: Group size Number of groups 2 254 3 168 4 52 5 21 6 6 What is the median group size?

Here is the ordered data of body temperatures (in degrees Fahrenheit) for 65 healthy adult women: 96.4, 96.7, 96.8, 97.2, 97.2, 97.4, 97.6, 97.7, 97.7, 97.8, 97.8, 97.8, 97.9, 97.9, 97.9, 98.0, 98.0, 98.0, 98.0, 98.0, 98.1, 98.2, 98.2, 98.2, 98.2, 98.2, 98.2, 98.3, 98.3, 98.3, 98.4, 98.4, 98.4, 98.4, 98.4, 98.5, 98.6, 98.6, 98.6, 98.6, 98.7, 98.7, 98.7, 98.7, 98.7, 98.7, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.9, 99.0, 99.0, 99.1, 99.1, 99.2, 99.2, 99.3, 99.4, 99.9, 100.0, 100.8 What is the first quartile of body temperatures for this data set?

Here is the ordered data of body temperatures (in degrees Fahrenheit) for 65 healthy adult women: 96.4, 96.7, 96.8, 97.2, 97.2, 97.4, 97.6, 97.7, 97.7, 97.8, 97.8, 97.8, 97.9, 97.9, 97.9, 98.0, 98.0, 98.0, 98.0, 98.0, 98.1, 98.2, 98.2, 98.2, 98.2, 98.2, 98.2, 98.3, 98.3, 98.3, 98.4, 98.4, 98.4, 98.4, 98.4, 98.5, 98.6, 98.6, 98.6, 98.6, 98.7, 98.7, 98.7, 98.7, 98.7, 98.7, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.8, 98.9, 99.0, 99.0, 99.1, 99.1, 99.2, 99.2, 99.3, 99.4, 99.9, 100.0, 100.8 Which value would need to be exceeded for a data point to be considered an outlier when using the 1.5 × IQR rule?

The distribution of ages of people in a class (to the nearest year) is as follows: Age 18 19 20 21 22 23 24 25 32 Number of students 14 120 200 200 90 30 10 2 1 What is TRUE about the median age (to the nearest year) of this distribution?

A sample was taken of the metabolic rates of men participating in a study regarding diets. The following boxplot depicts these rates (measured in kilocalories per 24 hours). Based on this boxplot, to which value is the interquartile range closest?