3. Calculate Mean deviation, Coefficient of M.D. from the following data
`73,70,71,73,68,67,69,72,76,71`

Solution:
Mean deviation :
Mean `bar x=(sum x)/n`

`=(73+70+71+73+68+67+69+72+76+71)/10`

`=710/10`

`=71`

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

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