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The following data about the sales and advertisement expenditure of a firms is given below (in ₹ Crores) What should be the advertisement expenditure if the firm proposes a sales target ₹ 60 crores?

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प्रश्न

The following data about the sales and advertisement expenditure of a firms is given below (in ₹ Crores)

  Sales Adv. Exp.
Mean 40 6
S.D. 10 1.5

Coefficient of correlation between sales and advertisement expenditure is 0.9.

What should be the advertisement expenditure if the firm proposes a sales target ₹ 60 crores?

योग
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उत्तर

Let X = Sales,

Y = Advertisement expenditure

Given, `bar x = 40, bar y = 6, sigma_"X" = 10, sigma_"Y" = 1.5`, r = 0.9

`"b"_"XY" = "r" sigma_"X"/sigma_"Y" = 0.9 xx 10/1.5 = 6`

`"b"_"YX" = "r" sigma_"Y"/sigma_"X" = 0.9 xx 1.5/10 = 0.135`

The regression equation of Y on X is

`("Y" - bar y) = "b"_"YX" ("X" - bar x)`

∴ (Y - 6) = 0.135(X - 40)

∴ Y - 6 = 0.135X - 5.4

∴ Y = 0.135X - 5.4 + 6

∴ Y = 0.135X + 0.6

For X = 60, 

Y = 0.135(60) + 0.6 = 8.1 + 0.6 = 8.7

∴ The advertisement expenditure should be ₹ 8.7 crores if the firm proposes a sales target ₹ 60 crores

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Properties of Regression Coefficients
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Linear Regression - Exercise 3.2 [पृष्ठ ४८]

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बालभारती Mathematics and Statistics 2 (Commerce) [English] Standard 12 Maharashtra State Board
अध्याय 3 Linear Regression
Exercise 3.2 | Q 11.2 | पृष्ठ ४८

संबंधित प्रश्न

For bivariate data. `bar x = 53, bar y = 28, "b"_"YX" = - 1.2, "b"_"XY" = - 0.3` Find estimate of Y for X = 50.


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You are given the following information about advertising expenditure and sales.

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Sales (₹ in lakh) (Y)
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Standard Mean 3 12

Correlation coefficient between X and Y is 0.8

  1. Obtain the two regression equations.
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  3. What should be the advertising budget if the company wants to attain sales target of ₹ 120 lakh?

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bYX + bXY = 1.30 and r = 0.75 


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The following data about the sales and advertisement expenditure of a firms is given below (in ₹ Crores)

  Sales Adv. Exp.
Mean 40 6
S.D. 10 1.5

Coefficient of correlation between sales and advertisement expenditure is 0.9.

Estimate the likely sales for a proposed advertisement expenditure of ₹ 10 crores.


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Variance of X = 9
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8x − 10y + 66 = 0
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  1. The mean values of X and Y.
  2. Correlation coefficient between X and Y.
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If the two regression lines for a bivariate data are 2x = y + 15 (x on y) and 4y = 3x + 25 (y on x), find

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Mean of x = 53

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