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Do larger universities tend to have more property crime? University crime statistics are affected by a variety of factors. The surrounding community, accessibility given to outside visitors, and many other factors influence crime rate. Let x be a variable that represents student enrollment (in thousands) on a university campus, and let y be a variable that represents the number of burglaries in a year on the university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents.
x | 14.3 | 31.8 | 24.5 | 14.3 | 7.5 | 27.7 | 16.2 | 20.1 |
y | 24 | 70 | 39 | 23 | 15 | 30 | 15 | 25 |
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(b) Use a calculator to verify that Σx = 156.4, Σx2 = 3510.46, Σy = 241, Σy2 = 9501 and Σxy = 5542.6.
Compute r. (Round to 3 decimal places.)
As x increases, does the value of r imply that y should tend to increase or decrease? Explain your answer.
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