1. Find Mean deviation about MEDIAN from the following data
`73,70,71,73,68,67,69,72,76,71`

Solution:
Median :
Observations in the ascending order are :
`67,68,69,70,71,71,72,73,73,76`

Here, `n=10` is even.

`M=(text{Value of } (n/2)^(th) text{ observation} + text{Value of } (n/2 + 1)^(th) text{ observation})/2`

`=(text{Value of } (10/2)^(th) text{ observation} + text{Value of } (10/2 + 1)^(th) text{ observation})/2`

`=(text{Value of }5^(th) text{ observation} + text{Value of }6^(th) text{ observation})/2`

`=(71 + 71)/2`

`=71`

`x`	`|x - M| = |x - 71|`
73	2
70	1
71	0
73	2
68	3
67	4
69	2
72	1
76	5
71	0
---	---
710	20

Mean deviation of Median
`delta bar x = (sum |x - M|)/n`

`delta bar x = 20/10`

`delta bar x = 2`


Coefficient of Mean deviation `=(delta bar x)/(bar x)`

`=2/71`

`=0.0282`

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2. Find Mean deviation about MEDIAN from the following data
`69,66,67,69,64,63,65,68,72`

Solution:
Median :
Observations in the ascending order are :
`63,64,65,66,67,68,69,69,72`

Here, `n=9` is odd.

`M=` value of `((n+1)/2)^(th)` observation

`=` value of `((9+1)/2)^(th)` observation

`=` value of `5^(th)` observation

`=67`

`x`	`|x - M| = |x - 67|`
69	2
66	1
67	0
69	2
64	3
63	4
65	2
68	1
72	5
---	---
603	20

Mean deviation of Median
`delta bar x = (sum |x - M|)/n`

`delta bar x = 20/9`

`delta bar x = 2.2222`


Coefficient of Mean deviation `=(delta bar x)/(bar x)`

`=2.2222/67`

`=0.0332`

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