Comparing Measures of Center and Variation

Use the dot plots representing the number of siblings of students in each class.

Visually Compare the 2 Dot Plots

• All the data are 7 siblings or fewer; There is a greater spread in the number of siblings in Mr. Walker’s class.

• All the data are 7 siblings or fewer; There is a greater spread in the number of siblings in Mr. Whites’s class.

• All the data are 6 siblings or fewer; There is a greater spread in the number of siblings in Mr. Walker’s class.

• All the data are 6 siblings or fewer; There is a greater spread in the number of siblings in Mr. Whites’s class

Use the dot plots representing the number of siblings of students in each class.

Compare the centers of the dot plots by finding the medians.

• The median for each class is 3.5

• The median for each class is 3

• The median for each class is 2

• The median for each class is 2.5

Use the dot plots representing the number of siblings of students in each class.

Compare the spreads of the dot plots by calculating the range

• The range for Mr. Walker’s class is 7 siblings; the range for Ms. White’s class is 5 siblings.

• The range for Mr. Walker’s class is 6 siblings; the range for Ms. White’s class is 5 siblings.

• The range for Mr. Walker’s class is 8 siblings; the range for Ms. White’s class is 5 siblings.

• The range for Mr. Walker’s class is 7 siblings; the range for Ms. White’s class is 6 siblings.

What can you infer Mr. Barrett's class about the shape of the Dot Plot?

• The data in Mr. Barrett’s have an outlier of 12, but the rest of the data are also clustered around 1 or 2 siblings.

• The data in Mr. Barrett’s have an outlier of 8, but the rest of the data are also clustered around 1 or 2 siblings.

• The data in Mr. Barrett’s have an outlier of 8, but the rest of the data are also clustered around 5 or 6 siblings.

• The data in Mr. Barrett’s have an outlier of 9, but the rest of the data are also clustered around 4 or 5 siblings.

What is the range of the dot plot for Mr. Barrett's class?

• The range for Mr. Barrett’s class is 8.5 siblings

• The range for Mr. Barrett’s class is 9 siblings

• The range for Mr. Barrett’s class is 6 siblings

• The range for Mr. Barrett’s class is 8 siblings

Compare the shapes of the box plots.

• Overall the scores of Class A are slightly higher, and the ranges of the box plots appear to be very similar.

• Overall the scores of Class B are slightly higher, and the ranges of the box plots appear to be very similar.

• Overall the scores of Class A are slightly higher, and the ranges of the box plots appear to be very far different.

• Overall the scores of Class B are slightly higher, and the ranges of the box plots appear to be very far different.

Compare the centers of the box plots.

• The median score for Class A is 5 points higher than for Class B.

• The median score for Class A is 10 points higher than for Class B.

• The median score for Class A is 10 points lower than for Class B.

• The median score for Class A is 5 points lower than for Class B.

Compare the spreads of the box plots.

• Class A has an IQR of 30, Class B has an IQR of 35. Both overall ranges are 70

• Class A has an IQR of 40, Class B has an IQR of 35. Both overall ranges are 80

• Class A has an IQR of 30, Class B has an IQR of 45. Both overall ranges are 80

• Class A has an IQR of 40, Class B has an IQR of 45. Both overall ranges are 70

The range of the number of M&M's is ______________ the range of the number of Skittles.

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What is the mode?

• Number that occurs the most

• The Average

• The difference between the highest and lowest values

• The Number in the middle