Let x be a random variable representing percentage change in neighborhood population in the past few years, and let y be a random variable representing crime rate (crimes per 1000 population). A random sample of six Denver neighborhoods gave the following information.
x  30  3  11  17  7  6 
y  170  35  132  127  69  53 
Σx = 74; Σy = 586; Σx^{2} = 1,404; Σy^{2} = 71,248; Σxy = 9,617
(a) Find x, y, b, and the equation of the leastsquares line. (Round your answers for x and y to two decimal places. Round your leastsquares estimates to three decimal places.)
x  =  
y  =  
b  =  
+ x(c) Find the sample correlation coefficient r and the coefficient of determination. (Round your answers to three decimal places.)

\
a)]
X̅=ΣX/n =  12.33 
Y̅=ΣY/n =  97.67 
b=4.864
ŷ =  37.682+4.864x 
c)
r=Cov/(Sx*Sy)=  0.911 
coefficient of determination r^{2} =  0.829 
percentage of variation in y is explained by the leastsquares model =82.9 %
d)
predicted value =37.682+4.864*15=  110.6 
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