Dr. Dentral is a dentist in London, Ontario and he has recorded the length of time that patients brush their teeth and the number of cavities that person had last week. The data is shown below. Year 2 3 4 5 Length of time brushing teeth in mins. 2.1 1.7 .3 .9 1.4 Number of Cavities 2 5 3 Given: n = 5 SumX = 6.4 SumY = 11 SumXY = 9 SumX2 = 10.16 SumY2 = 39