Answer:
3
Explanation:
To find the mean deviation about the mean of a set of data, you first need to find the mean of the data. The mean is calculated by adding all the values in the data set and dividing the sum by the number of values in the data set.
For the given data set, the mean is:
(3 + 6 + 5 + 7 + 10 + 12 + 15 + 18) / 8 = 72 / 8 = 9
To find the mean deviation about the mean, you need to take the absolute value of the difference between each value in the data set and the mean, and then find the mean of those differences.
For the given data set, the mean deviation about the mean is:
((|3 - 9| + |6 - 9| + |5 - 9| + |7 - 9| + |10 - 9| + |12 - 9| + |15 - 9| + |18 - 9|) / 8) = (24 / 8) = 3
So the mean deviation about the mean of the data set is 3.