Miss Cuihua and Mr. Xionger, two smart students at Abnormal Bear College (ABC), are very interested in examining the relationship between income and education for rural people working in cities. For that purpose, yesterday they went to a local electronics-assembling factory with a population of 852 workers from rural places. They randomly surveyed 25 workers with each worker's monthly salary (y, in RMB yuan) and education level (x, in years of formal schooling) recorded as follows, where, taking worker #3 for example, x3 = 5.0 and y3 = 3,300 imply that this surveyed worker had received 5 years of formal education with a current monthly salary of 3,300 yuan. Worker #: 1 1 2 3 4 Education Level: xi Monthly Salary: yi 9.0 6.0 4,100 5.0 3,450 3,300 4,050 10.9 24 25 4.5 10.5 3.250 4,300 Five sample sums have been calculated from the sample data as follows: 75, x = 201, 1 = 94,400, == 51 x = 1,768.5, ? = 361,365,000, 51 xiyi = 785,850.