MATH 110 Statistics Module 9 Exam Questions With Correct Answers

MATH 110 Statistics Module 9 Exam Questions
With Correct Answers
MATH 110 Statistics Module 9 Exam Questions
With Correct Answers

Portage Learning Math 110 Module 9 Exam
Exam Page 1
1. Suppose you have 45 data points and you calculate the sample correlation coefficient and find that
r = .32. Can you be 95% confident that a linear relation exists between the variables? If so, is the
relation positive or negative? Justify you answer.

Note that for n=45 and 95% we get a value from the chart of .29396. The absolute of r is |r|=.32,
which is above .29396. So a positive linear relation exists.

, MATH 110 Statistics Module 9 Exam Questions
With Correct Answers
Exam Page 2

2. Suppose you have 60 data points and you calculate the sample correlation coefficient and find that
r = .20. Can you be 95% confident that a linear relation exists between the variables? If so, is the
relation positive or negative? Justify you answer.

Note that for n=60 and 95% we get a value from the chart of .25420. The absolute of r is |r|=.20,
which is below .25420. So no linear relation exists.