Question

1. The following table gives the age of cars of a certain make and actual maintenance cost. Obtain the regression equation for costs related to age. Also estimate the maintenance cost for a ten years old car.
Age of car (Years) 2 4 6 8
Maintenance Cost(Rs. 10 20 25 30

Answer 1

Answer:

Let a=5,b=8,c=1

Here n=4

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x¯¯¯=a+cu¯¯¯=a+c.∑un=5+1×04=5

y¯¯¯=b+cv¯¯¯=b+c.∑vn=8+1×0.54byx=bvu=n∑uv−∑u∑vn∑u2−(∑u)2=4(19.5)−(0)(−0.5)4(20)−(0)2=0.975

Regression equation of y on x is y−y¯¯¯=byx(x−x¯¯¯) is

Y–7.875=0.975(x−5)

Y=0.975x+3

When x=9

Y=0.975(9)+3

=11.775

Step-by-step explanation: