Q5. (a) Natashah was studying the relationship between the price (RM y) of 1 kilogram of butter cake and the percentage of butter (x %) in the cake. Table 5.1 shows the data collected by Natashah for 8 brands of butter cake. Table 5.1 Brands A B C D E F G H X 10 20 20 y 35 55 55 55 40 30 30 35 70 40 100 80 60 90 40 50 60 70 60 90 110 130 =315 =620 x=1 =15225 = 56550 = 28750 (i) (iv) On a graph paper, draw a scatter diagram to represent the above data. (4 marks) Calculate the values of Sxx and Sy Hence, find the linear regression equation in the form of =a+bx. Correct all answers to two decimals places. (6 marks) Draw the regression line from Q5. (a) (ii) on the scatter diagram drawn in Q5. (a) (i). (1 mark) Natashah believes that one brand of butter cake is overpriced. State which brand is overpriced and justify your answer. Suggest a fair price for this brand. (4 marks)