183k views
0 votes
What is the r-value of the following data, to three decimal places?

X, 4 5 8 9 13
Y, 26, 11, 13, 2, 1
O A. -0.686
OB. 0.828
O C. 0.686
O D. -0.828​

1 Answer

5 votes

Answer:

The correct option is D

D) -0.828

Explanation:

Step 1:

First find the mean of both x data set and y data set

x(mean) = 39/5 = 8

y(mean) = 53/5 = 11

Step 2:

(find the values given in table attached below. The formation of table is step 2)

Step 3:

Substitute ∑x, ∑y, ∑xy, ∑x² & ∑y² value in the below correlation coefficient formula

r = ∑XY/(√∑X². ∑Y2²

∑XY = -119.4,∑X² = 50.8, ∑Y² = 409.2

r = -119.4/(√50.8 x 409.2)

Simplify above expression

r = -119.4/√20787.36

r = -119.4/144.1782

r = -0.8281

Thus -0.8281 is the correlation between x = {4, 5, 8, 9 and 13} & y = {26, 11, 13, 2 and 1}

What is the r-value of the following data, to three decimal places? X, 4 5 8 9 13 Y-example-1
User Zartog
by
4.8k points