Compare Variability

What inference can you draw by comparing the data?

• There is more variability in the number of days that Team A members trained because the range for Team A is greater than the range for Team B.

• 75% of Team A's training was between 5 and 20 days.

• The interquartile range of Team B is about 20 days.

• Team A generally spends more time training since they have a higher median.

What is the difference between the maximum number of hours that Zach and Steven have spent on their homework?

• 0.5

• 0.75

• 2.5

• 3

Which of the following statements is true?

• Group 1 has a greater median number of hours that they watched television. Group 1 has a smaller IQR, so the data is less spread out.

• The mean for group 2 is larger than the mean for group 1.

• The median for group 2 is larger than the median for group 1.

• Both sets of data are symmetric. You should use the mean to compare the measures of center.

Which class had the greater range of scores?

• Room 300

• Room 240

Which class shows more consistent test scores?

• Room 300 because of a larger range.

• Room 240 because of a larger range.

• Room 300 because of a smaller range.

• Room 240 because of a smaller range.

The double dot plots show the average wait times in minutes for two popular rides at an amusement park. Compare the measures of center and variation, which ride typically has a longer wait time?

• No inference can be made from the graph.

• Topsy Turvy

• The wait times are the same for both rides.

• Rocket Blast

• The median for the fruit data is 100. The median for the vegetable data is 50. Fruits have a higher number for calories with greater variation.

• The median for the fruit data is 50. The median for the vegetable data is 100. Fruits have a higher number of calories with greater variation.

• The median for the fruit data is 100. The median for the vegetable data is 50. Vegetables have a higher number of Calories with a greater variation.

• The median for the fruit data is 100. The median for the vegetable data is 50. Fruits have a higher number for calories with less variation.

Roger compares the goals scored per game by Team A and Team B. What do the box plots tell you about the variability of the data? (Hint: look at the length of the rectangle)

• The data for Team A has greater variability than the data for Team B because Team A's maximum is higher than Team B's maximum.

• The data for Team B may have greater variability than the data for Team B because Team B's range is greater than Team A even though their IQR is the same.

• The data for Team A and Team B have about the same variability because they both have the same IQR and the same range.

• The data for Team A has greater variability because there is a greater range between the maximum and the minimum for Team A than for Team B.

Answer explanation

The data for Team B may have greater variability than the data for Team A because Team B's range is greater than Team A even though their IQR is the same.

Braden is comparing statistics about the prices of DVD players from two different stores. Compare the variability of the data of each store. Select ALL correct statements.

• The range and IQR are greater at Store B as compared to Store A.

• The range and IQR are greater at Store A as compared to Store B.

• There is more variability, or spread, in prices of DVD players at Store A.

• There is more variability, or spread, in prices of DVD players at Store B.

Answer explanation

The range and IQR are greater at Store A as compared to Store B. There is more variability, or spread, in prices of DVD players at Store A.

Keyli gathers the heights of a random sample of six graders and seventh graders and displays the data in box plots. What can she say about the data sets?

• The 6th grade sample has greater variability.

• The 7th grade sample has greater variability.

• The 6th grade sample has the greater median.

• The ranges are equal for both samples.