Find the mean deviation of the set of numbers 4, 5, 9

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.