Question

A chemist wishes to study the relationship between the drying time of a paint and the concentration of a base solvent that facilitate a smooth application. The data of concentration setting(x) and the observed drying time in minutesly) are recorded and the summary data are calculated. The Average and Standard deviation for x and y in usual notation for the above data set: -2, sdx-1.6, 5-5, sdy-3.2 and the correlation coefficient 0.8 Find the linear regression equation, y=0.3x+1.6 y=-1.6x+03 y=16x+18 y=1.8x+16 None of the above

Answer 1

Formula for Regression equation is (y-7)=9 quation is ( Y) sd, * "(x-7). From the given information, The correlation value is r=0.8 = 2 sd = 1.6 J = 5 sd, = 3.2 Substitute the given values in the regression equation, (y-7)= "XI, (x=F) (1-5) = 0.843.2 (x-2) sd y-5=1.6(x-2) y-5=1.6x – 3.2 y=1.6x-3.2 +5 y =1.6x +1.8 Thus, the correct option is y=1.6x +1.8.