The ages of 5 friends are: 11, 9, 12, 10, 11. What is the mean absolute deviation of the ages?

Answer 1

To find the mean absolute deviation (MAD) of the ages, follow these steps:

1. Find the mean (average) of the ages:
(11 + 9 + 12 + 10 + 11) / 5 = 53 / 5 = 10.6

2. Find the absolute deviation of each age from the mean:
|11 - 10.6| = 0.4
|9 - 10.6| = 1.6
|12 - 10.6| = 1.4
|10 - 10.6| = 0.6
|11 - 10.6| = 0.4

3. Find the mean of the absolute deviations:
(0.4 + 1.6 + 1.4 + 0.6 + 0.4) / 5 = 4 / 5 = 0.8

Therefore, the mean absolute deviation of the ages is 0.8.