Does studying for an exam pay off? The number of hours studied, x, is compared with the exam grade received, y.

x 7 7 5 5 7
y 95 90 75 85 95

(a) Complete the preliminary calculations: SS(x), SS(y), and SS(xy).
Incorrect: Your answer is incorrect. . (SS(x))
Incorrect: Your answer is incorrect. . (SS(y))
Incorrect: Your answer is incorrect. . (SS(xy))

(b) Find r. (Give your answer correct to three decimal places.)
Can someone help me and my friend we have worked this out several times come up with the same answers but it is wrong. We would like to see where we are doing it wrong.

Thanks but I do not need your help on this one anymore...

To complete the preliminary calculations, we need to calculate SS(x), SS(y), and SS(xy).

To calculate SS(x), we need to find the sum of the squared differences between each x value and the mean of x.

First, let's calculate the mean of x:
Mean of x = (7 + 7 + 5 + 5 + 7) / 5 = 31 / 5 = 6.2

Now, let's calculate the squared differences for each x value:
(7 - 6.2)^2 = 0.64
(7 - 6.2)^2 = 0.64
(5 - 6.2)^2 = 1.44
(5 - 6.2)^2 = 1.44
(7 - 6.2)^2 = 0.64

Summing up these squared differences, we get:
SS(x) = 0.64 + 0.64 + 1.44 + 1.44 + 0.64 = 4.8

So, the correct answer for SS(x) is 4.8.

Similarly, we can calculate SS(y) by finding the sum of the squared differences between each y value and the mean of y.

First, calculate the mean of y:
Mean of y = (95 + 90 + 75 + 85 + 95) / 5 = 440 / 5 = 88

Now, calculate the squared differences for each y value:
(95 - 88)^2 = 49
(90 - 88)^2 = 4
(75 - 88)^2 = 169
(85 - 88)^2 = 9
(95 - 88)^2 = 49

Summing up these squared differences, we get:
SS(y) = 49 + 4 + 169 + 9 + 49 = 280

So, the correct answer for SS(y) is 280.

To calculate SS(xy), we need to find the sum of the product of the differences between each x and the mean of x and y and the mean of y.

First, calculate the mean of x and y:
Mean of x = 6.2
Mean of y = 88

Now, calculate the product of the differences for each x and y value:
(7 - 6.2)(95 - 88) = 0.56 (rounded to two decimal places)
(7 - 6.2)(90 - 88) = 0.32 (rounded to two decimal places)
(5 - 6.2)(75 - 88) = -1.44 (rounded to two decimal places)
(5 - 6.2)(85 - 88) = -0.64 (rounded to two decimal places)
(7 - 6.2)(95 - 88) = 0.56 (rounded to two decimal places)

Summing up these products, we get:
SS(xy) = 0.56 + 0.32 - 1.44 - 0.64 + 0.56 = -0.64

So, the correct answer for SS(xy) is -0.64.

Now, let's move on to finding r, the correlation coefficient.