Question

Consumers Union provides ratings on a large variety of consumer products. They use sophisticated testing methods as well as surveys of their members to create these ratings.

   

One recent article rated laundry detergents on a scale from 1 to 100. Here are the ratings along with the price per load, in cents, for 24 laundry detergents:

   

Rating	Price (cents)
60	18
55	30
48	16
46	13
35	8
32	5
59	22
52	23
46	15
46	13
34	12
29	14
56	22
51	11
48	18
45	17
33	7
26	11
55	17
50	15
46	13
36	8
32	6
26	13

   

Use these data to compute the correlation between rating and the price per load.

   

   

(Use decimal notation. Give your answer to three decimal places.)

Answer 1

	Rating (X)	Price (cents) (Y)	X * Y	X2	Y2
	60	18	1080	3600	324
	55	30	1650	3025	900
	48	16	768	2304	256
	46	13	598	2116	169
	35	8	280	1225	64
	32	5	160	1024	25
	59	22	1298	3481	484
	52	23	1196	2704	529
	46	15	690	2116	225
	46	13	598	2116	169
	34	12	408	1156	144
	29	14	406	841	196
	56	22	1232	3136	484
	51	11	561	2601	121
	48	18	864	2304	324
	45	17	765	2025	289
	33	7	231	1089	49
	26	11	286	676	121
	55	17	935	3025	289
	50	15	750	2500	225
	46	13	598	2116	169
	36	8	288	1296	64
	32	6	192	1024	36
	26	13	338	676	169
Total	1046	347	16172	48176	5825

r = 0.725