Finding and Comparing of Center and Spread

Given the data: 21, 31, 26, 24, 28, 26
This is a 3 part question:
Part-1: What is the mean of the data?

• 24

• 25

• 26

• 27

Given the data: 21, 31, 26, 24, 28, 26
This is a 3 part question:
Part-2: Find the standard deviation of 21, 31, 26, 24, 28, 26.

• S.D. ≈ 9.67

• S.D. ≈ 26

• S.D. ≈ 3.1

• S.D. ≈ 10

Given the data: 136, 150, 119, 150, 125, 143.
Find the interquartile range (IQR)

•  IQR = 150 - 119 = 31

•  IQR = 150 - 125 = 25.

• IQR = 150 - 125 = 75.

•  IQR = 150 - 119 = 31.

• Mode
• Median
• Mean
• IQR

• 13.6
• 2.2
• 15.8
• 68.2

Quartiles are values that divide a data set into four equal parts.

• True

• False

The interquartile range (IQR) of a data set is the difference between the third and first quartiles. It represents the range of the middle half of the data.

• True

• False

Given the data: 136, 150, 119, 150, 125, 143.
Find the range. 

• Range = 136 - 125 = 21.

• Range = 150 - 125 = 75.

• Range = 150 - 125 = 25.

• Range = 150 - 119 = 31

Which of the following best describes the shape of the distribution?

• skewed left

• skewed right

• uniform

• symmetrical

Should we use the mean or the median to represent the center of the data?