R = -0.90 (2 decimal places)
Step-by-step explanation:
Given the data :
Speed (Miles per Hour) :
30
50
40
55
30
25
60
25
50
55
Miles per Gallon :
29
26
26
22
29
31
21
35
25
26
The correlation Coefficient, R shows the degree or level of relationship between the dependent and independent variable. A positive R value denotes a positive correlation while a negative R value denotes a negative relationship. R values should range between - 1 to +1 with values close to 1 and - 1 depicting strength while value of zero means no relationship exist.
Hence, R value of -0.90 depicts a strong negative relationship. Hence, higher speed are related to lower miles per gallon and vice versa.