Compute mean deviation and its coefficient from mean of following frequency data: | Statistics | SciPiPupil

Question: Compute mean deviation and its coefficient from mean of  following frequency data:

Mid Wages (RS.)	20	25	30	35	40
No. of workers	2	5	6	5	2

Solution:

Arranging data in a table,

Mid Value(x)	Frequency (f)	fx	|x-x̄|	f|x-x̄|
20	2	40	10	20
25	5	125	5	25
30	6	180	0	0
35	5	175	5	25
40	2	80	10	20
	N=20	$\sum$|x-x̄| = 600		$\sum$fx|x-x̄| = 90

Now,

Mean (x̄) =$\dfrac{\sum fx}{N}$

$= \dfrac{600}{20}$

$= 30$

And,

Mean Deviation from Mean (M.D.) = $\dfrac{\sum f|x-x̄|}{N}$

$= \dfrac{90}{20}$

$= 4.5$

Also,

Coefficient of M.D. = $\dfrac{M.D.}{x̄}$

$= \dfrac{4.5}{30}$

$= 0.15$

Hence, the required mean deviation about the mean of the given data is 4.5 and coefficient of mean deviation is 0.15.

Related Notes and Solutions:

Here is the website link to the notes of Statistics of Class 10.

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