Find the mean deviation of the set of numbers 4, 5, 9
Answer Details
To find the mean deviation of a set of numbers, we first need to find the mean or average of those numbers.
The mean of the numbers 4, 5, and 9 is:
(mean) = (4 + 5 + 9) / 3 = 6
Next, we need to find the deviation of each number from the mean. To do this, we subtract the mean from each number:
4 - 6 = -2
5 - 6 = -1
9 - 6 = 3
To avoid positive and negative deviations cancelling out, we take the absolute value of each deviation:
| -2 | = 2
| -1 | = 1
| 3 | = 3
Then, we find the mean of these absolute deviations by summing them up and dividing by the number of numbers:
(2 + 1 + 3) / 3 = 2
Therefore, the mean deviation of the set of numbers 4, 5, 9 is 2.
So, the correct option is 2.