Question

Find the coefficient of correlation for the following: 

Cost (Rs)	14	19	24	21	26	22	15	20	19
Sales (Rs)	31	36	48	37	50	45	33	41	39

Answer 1

X	Y	x= X - \(\bar{X}\) = X - 20	y = Y - \(\bar{Y}\) = Y - 40	x2	y2	xy
14	31	-6	-9	36	81	54
19	36	-1	-4	1	16	4
24	48	4	8	16	64	32
21	37	1	-3	1	9	-3
26	50	6	10	36	100	60
22	45	2	5	4	25	10
15	33	-5	-7	25	49	35
20	41	0	1	0	1	0
19	39	-1	-1	1	1	1
180	360	0	0	120	346	193

Correlation coefficient