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Question 40 of 41
Q.

The profit earned (in lakh ₹\text{\text{₹}}) by a company making computers is as follows. Find the linear equation for the trend from these data by least square method and estimate the profit for the year 2017:

Year20112012201320142015
Profit (lakh ₹\text{\text{₹}})3135394144
Gujarat GsebGujarat Board (GSEB) HSC Commerce Board 2026Subjective· 5mImportance★★★★★
98% · 40/41 Questions
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With x=x= year−2013-2013: Σx=0,Σy=190,Σxy=32,Σx2=10\Sigma x=0,\Sigma y=190,\Sigma xy=32,\Sigma x^2=10; a=yˉ=38, b=3210=3.2a=\bar y=38,\ b=\tfrac{32}{10}=3.2; y^=38+3.2x\hat y=38+3.2x; for 2017 (x=4x=4), y^=50.8\hat y=50.8.

Let x=year−2013x=\text{year}-2013 so that Σx=0\Sigma x=0.

Yearyyxxxyxyx2x^2
201131−2-2−62-624
201235−1-1−35-351
201339000
2014411411
2015442884
Sum19003210

Since Σx=0\Sigma x=0, the least-squares constants are …

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