Find the mean deviation about the mean for the data 4, 7, 8, 9, 10, 12, 13, 17

Solution:

The given data is 4, 7, 8, 9, 10, 12, 13, 17.

Mean of the data

= (4 + 7 + 8 + 9 + 10 + 12 + 13 + 17) / 8

= 80 / 8

= 10

The deviations of the respective observations from the mean x,

i.e., x_i - x are

- 6, - 3, - 2, - 1, 0, 2, 3, 7

The absolute values of the deviations, |x_i - x| are 6, 3, 2, 1, 0, 2, 3, 7

The required mean deviation about the mean is

M.D. (x) = ⁸∑_{i = 1} (|x_i - x|) / 8

= (6 + 3 + 2 + 1 + 0 + 2 + 3 + 7) / 8

= 24/8

= 3

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NCERT Solutions Class 11 Maths Chapter 15 Exercise 15.1 Question 1

Find the mean deviation about the mean for the data 4, 7, 8, 9, 10, 12, 13, 17

Summary:

The mean deviation about the mean for the given data is 3