Question 965515
We are given the following information
x-axis(People) 2, 1, 5, 6, 4, 1, 2, 5
y-axis(Bill**) 1, 0.25, 2.5, 3.5, 1.8, 0.45, .75, 3
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a) the points are graphed with their x, y coordinates, for example
(2, 1) is the first of 8 points
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b) This is a linear regression problem without a y intercept (no x value = 0)
The general form of the equation is y = b*x where 
b = (summation from i = 1 to 8 of xi*yi) / (summation from i = 1 to 8 of xi^2)
b = (2×1)+(1×0.25)+(5×2.5)+(6×3.5)+(4×1.8)+(1×0.45)+(2×0.75)+(5×3) / 2²+1²+5²+6²+4²+1²+2²+5²
b = 59.9 / 112 = 0.534821429
therefore the regression equation is
y = 0.534821429 * x, where * means multiply
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the trend line is a good fit if
1) same number of point above the line as below the line
2) are they evenly distributed
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c) our equation is
y = 0.534821429 * x
we are asked what is x for 150, then y = 150 / 100 = 1.5
1.5 = 0.534821429 * x
x = 1.5 / 0.534821429
x = 2.804674457 approx 3
size of household is 3 people