What is the r-value of the following data to three decimal places?
x
y
2 15
6 13
7 9
8 8
12 5
a. 0.953
b. -0.953
c. 0.909
d. -0.909

Option B

Step-by-step explanation:

Given that two variables in table as

                                            Total     Average

x              2   6   7   8   12       35          7

y             15  13   9   8    5        50         10

xy            30 78 63 64  60     295        59

(x-7)^2   25      1  0     1   25        52     10.4

(y-10)^2   25   9   1      4   25     64        12.8

Var x = 10.4 and std dev x = 3.225

Var Y = 12.8 and std dev Y = 3.578

Cov (xy) = E(xy)-E(x) E(Y)=59-70=-11

Correlation coefficient r

= Cov /sx sy = -11/(3.225)(3.578)=-0.9532

Round off to get

r=-0.953

Henceoption B is right.

5y

step-by-step explanation: