-Compute the sample correlation coefficient between the price and the number of flash drives sold. Also,...

-Compute the sample correlation coefficient between the price and the number of flash drives sold. Also, develop a least-squares estimated regression line.

Price (x)	Units sold (y)
34	4
36	4
32	6
35	5
31	9
38	2
39	1

Expert Solution

Solution :

X	Y	XY	X^2	Y^2
34	4	136	1156	16
36	4	144	1296	16
32	6	192	1024	36
35	5	175	1225	25
31	9	279	961	81
38	2	76	1444	4
39	1	39	1521	1

n	7
sum(XY)	1041.00
sum(X)	245.00
sum(Y)	31.00
sum(X^2)	8627.00
sum(Y^2)	179.00
Numerator	-308.00
Denominator	326.02
r	-0.9447
r square	0.8925

Xbar(mean)	35.0000
Ybar(mean)	4.4286
SD(X)	2.3570
SD(Y)	2.1602

b	-0.8462
a	34.0440

sample correlation coefficient = r = -0.9447

Regression line = 34.0440 - 0.8462 x

orchestra answered 2 years ago

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