Part C: Thinking (10 marks) 7) Consider the table to the right that shows the number of Radio advertisements (x) and number of home sales (y). X y xy x2 y2 a)Complete the table [3 marks] 10 7 10X7= 70 102 = 100 72= 49 b) Find the equation of the line of best fit 12 12 12x 12= 144 122= 144 1 122 = 144 manually (SHOW YOUR WORK) [2 marks] 9 16 9 x 16= 144 92 = 81 162 = 256 15 20 15 x 20 = 300 152 = 225 202=400 13 21 13x 21 = 273 132= 169 212 = 441 20 28 20*28=560/ 202= 400 282= 784 22 29 22x 29= 638/ 222 = 484 292 = 841 20 30 20x 30 =600 202 = 400 | 303 = 900 Ex=121 Ey= 163 [xy= 2,729 [x 2= 2,003 [yz=3, 815 c) If the manager of the company wants to sell 120 homes, how many advertisements does he need to make? [1 marks] 8) Find the combined average of all three biology classes summarized in this table [2 marks] Section SBI3C11 SBI3C12 SBI3C13 # Students 28 30 32 Average 87 84 72 9)The average of 7 numbers is 69. When the two numbers b and 3b were included with these 7 numbers the average for all 9 numbers becomes 67. Find these two numbers b and 3b [2 marks]