PRECALC CORRELATION VALUE QUESTION

Question

The following ordered pairs give the entrance exam scores 𝑥 and the grade-point averages 𝑦 after 1 year of college for 10 students.



a) Find the correlation value, r, for the variables.

b) Do you believe there is a linear relationship between the variables? Why?

c) Find the equation of a line that models entrance exam scores and GPA.

d) Interpret the slope of the line in a relationship of the problem.

e) Find the predicted GPA for someone who scored an 84 on the entrance exam.

x	y
75	2.3
82	3
90	3.6
65	2
70	2.1
88	3.5
93	3.9
69	2
80	2.8
85	3.3

Answer 1

So Cayley, what would you like to know how to do? We are more value to you if we show you how than by giving you the answer. Are you blocked on:

(a) calculate the correlation coefficient between two variables?

(b) graph a scatter diagram for the two data series? Inspect it for evidence for, or against, there bein a roughly linear relationship?

(c) fit a least-squares best fit line to the data?

(d) interpret the slope of that line?

(e) use the formula for that line to interpolate the y value for a particular x value?

How far did you get? Where is your roadblock?

Ed