What is the mean of the following grouped data? Use 3 sig figs as needed. Grades Frequency 40-49 3 50-59 5 60-69 6 70-79 9 80-89 8 90-100 7 mean =An archer has a 90% chance of hitting a target with arrows. If 5 arrows are fired, determine the chance of hitting the target: In) at most 3 times E The probability of drawing an ace or face card from a standard deck of cards is considered a event.The annual income and average weekly grocery bill for a selection of families is shown below. Income (x thousand pounds) 55 36 25 47 60 64 42 50 Grocery bill (y pounds) 120 90 60 160 190 250 110 150 Find the regression line of y against x. y =