Measures of Dispersion Class 11 OP Malhotra Exe-21A ISC Maths Ch-21 Solutions. In this article you would learn about Computation of Mean Deviation. Step by step solutions of latest textbook has been given as latest syllabus. Visit official Website CISCE for detail information about ISC Board Class-11 Mathematics.

Measures of Dispersion Class 11 OP Malhotra Exe-21A ISC Maths Solutions Ch-21

Board	ISC
Publications	S Chand
Subject	Maths
Class	11th
Chapter-21	Measures of Dispersion
Writer	O.P. Malhotra
Exe-21(A)	Computation of Mean Deviation.

Computation of Mean Deviation.

Measures of Dispersion Class 11 OP Malhotra Exe-21A ISC Maths Ch-21 Solutions.

From the following data, using mean, calculate mean deviation and the coefficient of mean deviation.

Que-1: 15, 17, 19, 25, 30, 35, 48

Sol:  The table of values is given as under :

Que-2: 21, 23, 25, 28,30, 32, 38, 39, 46, 48

Sol: Here Mean x⃗ = (21+23+25+28+30+32+38+39+46+48)/10 = 330/10 = 3
The table of values is given as under:

∴ M.D. about Mean = Σ|di| / n = 78/10 = 7.8
and coeff. of M.D. = M.D / x¯ = 7.8/33 = 0.236

Que-3: 10, 70, 50, 53, 20, 95, 55, 42, 60, 48, 80
Calculate the mean deviation from the mean for the following frequency distributions.

Sol: Mean x¯ = (10+70+50+53+20+95+55+42+60+48+80)/11 = 583/11 = 53

∴ required M.D about Mean = Σ|di| / n = 190/11 = 17.27
and coeff. of M.D = M.D / Mean = 190/(11×53) = 0.32

Que-4:

Sol: 

∴ Mean x¯ = Σfixi / Σfi = 660/44 = 15
Thus M.D about Mean = Σfi|di / |Σfi = 312/44 = 7.09
Que-5:

Sol: The table of values is given as under :

∴ x¯ = 576/48 = 12
∴ M.D about Mean = Σfi|di| / 48 = 36/48 = 3/4 = 0.75

Que-6:

Sol: We construct the table of values is given as under :

∴ by direct method, mean x¯ = ∑fixi / ∑fi = 1350/50 = 27
Thus, M.D from mean = [Σfi|xi−x¯] / |Σfi = 472/50 = 9.44

Que-7:

Sol: The table of values is given as under:

∴ Mean = Σfixi / Σfi = 8560/50 = 171.2
Thus M.D about mean = Σfi|di| / Σfi = 528/50 = 10.56

Que-8:

Sol: 

∴ Mean x¯ = Σfixi / Σfi = 9200/182 = 50.55
∴ M.D about mean = Σfi|di| / Σfi = 2390.6/182 = 13.135

Que-9: 3, 9, 5, 3, 12, 10, 18, 4, 7, 19, 21

Sol: Arranging the data in ascending order, we get 3, 3, 4, 5, 7, 9, 10, 12, 18, 19, 21
Here no. of observations = n = 11 (odd)
∴ Md = {(n+1)/2}th observation = 6th observation = 9

∴ M.D about median = Σ|xi−Md| / n = 58/11 = 5.273
and Coefficient of M.D = M.D / Median = 58/(11×9) = 0.586

Que-10: 100, 150, 200, 250,360, 490, 500, 600, 671

Sol: Data given is already in ascending order we have, no. of observations = n = 9 (odd)
∴ Md = {(n+1)/2}th observation = 5th observation = 360

∴ M.D about median = Σ|xi−Md| / n = 1561/9 = 173.44
and Coeff. of M.D = M.D / median = 1561/(9×360) = 0.48

Que-11:

Sol: The table of values is given as under :

Que-12:

Sol: The table of values is given as under :

–: End of Measures of Dispersion Class 11 OP Malhotra Exe-21A ISC Maths Ch-21 Solutions. :–

Return to :- OP Malhotra ISC Class-11 S Chand Publication Maths Solutions

Thanks

Please share with your friends