QUESTION 10 A director of alumni affairs at a small college wants to determine whether there is a (7 marks) linear relationship between the number of years alumni have been out of school and their annual contributions (in thousands of dollars). The data are shown in the table below. Number of years 10 15 24 30 out of school, x Annual contribution 12.5 8.7 14.6 5.2 90 3.1 2.7 (in 1000s of $), y Calculate the correlation coefficient for the number of years out of school and annual contribution data. Interpret the result in the context of the data I QUESTION 11 A study says the mean time to recoup the cost of bariatric surgery is 3 years. You (8 marks) randomly select 25 bariatric surgery patients and find that the mean time to recoup the cost of their surgeries is 3.3 years. Assume the population standard deviation is 0.5 year and the population is normally distributed. Is there enough evidence to doubt the study's claim at a = 0.01? OMULUIIVIVO The graph below shows the best fit line of the data of work time, x, against leisure time, y, in hours per week. (in hours per week) Leisure time H 40 42 44 46 48 50 52 Work time (in hours per week) a. Describe the type of correlation of the data and give the range values of r. (2 marks) b. Given the equation of the regression for the given data as: D = mx + 52.6 i. Find the gradient, m, when the work time is 47 hours per week and the (3 marks) expected leisure time is 21.25 hours per week. ii. Predict the expected hour of leisure time when the work hour is 51 hours (3 marks) per week