Question

1. For cach of the data sets shown below, calculater. (6) X y 16 27 3 5 21 3 4 4 3

Answer 1

1)

a)

X	Y	XY	X^2	Y^2
1	6	6	1	36
2	7	14	4	49
3	5	15	9	25
4	4	16	16	16
5	3	15	25	9
6	1	6	36	1
7	2	14	49	4

n	7
sum(XY)	86.00
sum(X)	28.00
sum(Y)	28.00
sum(X^2)	140.00
sum(Y^2)	140.00
Numerator	-182.00
Denominator	196.00
r	-0.9286
r square	0.8622
Xbar(mean)	4.0000
Ybar(mean)	4.0000
SD(X)	1.7078
SD(Y)	1.9720
b	-0.9286
a	7.7143

(3)-(«) (3)-(3) ... (3)() - -

r = -0.93

(b)

X	Y	XY	X^2	Y^2
1	2	2	1	4
2	1	2	4	1
3	4	12	9	16
4	3	12	16	9
5	7	35	25	49
6	5	30	36	25
7	6	42	49	36

n	7
sum(XY)	135.00
sum(X)	28.00
sum(Y)	28.00
sum(X^2)	140.00
sum(Y^2)	140.00
Numerator	161.00
Denominator	196.00
r	0.8214
r square	0.6747
Xbar(mean)	4.0000
Ybar(mean)	4.0000
SD(X)	1.7078
SD(Y)	1.9720
b	0.8214
a	0.7143

r = 0.82

(c)

X	Y	XY	X^2	Y^2
1	7	7	1	49
2	6	12	4	36
3	5	15	9	25
4	4	16	16	16
5	3	15	25	9
6	2	12	36	4
7	1	7	49	1

n	7
sum(XY)	84.00
sum(X)	28.00
sum(Y)	28.00
sum(X^2)	140.00
sum(Y^2)	140.00
Numerator	-196.00
Denominator	196.00
r	-1.0000
r square	1.0000
Xbar(mean)	4.0000
Ybar(mean)	4.0000
SD(X)	1.7078
SD(Y)	1.7078
b	-1.0000
a	8.0000

r = -1.00