Mean Absolute Deviation

True or False.  Deviation is a measure of difference between the observed value of a variable and some other value.

• True
• False

The list shows the number of songs that five students each downloaded last week.
32, 43, 38, 28, 51
What is the mean absolute deviation of the numbers in the list?

• 3.14
• 6.88
• 38.4
• 7.68

The list shows the number of songs that five students each downloaded last week. 
68, 72, 77, 64, 69, 76
What is the mean absolute deviation of the numbers in the list?

• 71
• 24
• 4
• 13

Mary was trying to compute the mean absolute deviation for the following data:
62, 66, 71, 58, 63, 70
She determined the mean was 65.
What is the next step?

• Divide 65 by 6.
• Add 65 to each data.
• Find the absolute difference between the mean and the data.
• Nothing she is done