Assume the car expert requested estimates of the mean number of days to sell for the Domestic cars with a margin of error of seven days and the mean selling price of foreign cars with a margin of error of eight days.

• Using 98% confidence, how large should the sample sizes be for each one?
• How could the sample size formula be useful in understanding both types of car businesses? What are some advantages of a larger sample size?
• Suppose a Domestic car has a list price of $30,000 and a Foreign car has a list price of $30,000. What is your estimate of the final selling price (based on the percent difference for the sale and list price) and number of days required to sell each of these cars?

	Domestic Cars		Foreign Cars
Car	List Price in K	Sale Price in K	Days to Sell		List Price in K	Sale Price in K	Days to Sell
1	9	8.3	40		36.7	34.1	39
2	34	30.2	5		52	51.5	26
3	23.9	19.3	48		11.1	9.6	27
4	29.7	28.8	12		48.1	45.9	52
5	26.7	24.1	28		6.8	4.5	53
6	31.2	31.2	30		7.5	6.5	39
7	22.7	20.2	24		71.5	70.8	59
8	8	4	42		21.7	21.7	51
9	18.3	14.9	29		59.5	59.1	40
10	43.9	42.9	16		19.1	17.7	15
11	49.1	47.1	23		67	64.3	46
12	8.7	5.4	17		79.2	76.1	62
13	23.2	18.3	30		29.3	24.9	32
14	17.1	13.4	15		69.1	66	55
15	15.3	14.5	40		63.9	58.9	15
16	39.7	35.2	31		54.5	51.2	46
17	12.4	9.2	27		61.4	56.4	20
18	42.3	40.3	58		70.8	69.8	24
19	25	24.2	19		29.2	28.4	5
20	36.2	34.8	30		26.6	23.9	44
21	13.9	12.1	37		11.7	9	58
22	18.7	15.6	43		12.2	8.5	11
23	39.5	36.6	44		51.6	50.6	36
24	23	22.1	55		48.8	48.4	24
25	32	31	40		33.9	32.4	31
26	34.9	33.1	22		82.3	77.8	51
27	43.6	39.2	56		75.9	71.8	21
28	6.9	4.7	28		44.1	39.7	17
29	43.6	41.8	47		30.5	27.7	35
30	12	9.6	44		56.5	52.3	19
31	8.7	6.1	13		88.3	88	18
32	7.2	5.3	15		51.8	50.8	46
33	39.6	36	47		25.7	21.6	8
34	16.5	16.2	21		34.2	33.1	42
35	43.9	40.8	45		75.8	75.3	24
36	47.6	46.2	5		75.5	73.5	25
37	21.3	21	44		40	39.6	55
38	29.5	26.9	6		67	66.2	50
39	18.6	16.2	47		16	15	22
40	46.6	46	60		50.2	46.1	40
41	8	6.1	14		85.1	83.8	52
42	11.2	8.6	13		73	71.2	22
43	33.8	32.6	28		15	11.6	37
44	10.1	7.2	30		12.9	10.6	32
45	13.9	13.6	15		26.3	22	27
46	48.4	44.5	28		29.8	28.5	16
47	13.5	13.1	46		65.7	62.4	4
48	6.4	4.2	45		21.8	19.4	43
49	38.3	38.2	37		44.3	40.5	9
50	38.5	37.7	40		78.6	77.2	61
51	36.9	36.4	43		50	49.2	45
52	18.6	14.1	25		57.1	53.8	23
53	4.5	3.1	47		46.6	45.6	58
54	25.4	22.5	38		82.2	78.6	66
55	59.9	57.3	58		61.1	58.3	61
56	44	40.5	53		81	78.9	35
57	19.8	18.3	18		77.1	75.3	44
58	12.6	10.1	20		34.4	29.4	23
59	35	31.8	11		23	22.5	4
60	52.2	49.9	49		54.9	53.9	57
61	38.6	36.6	50		82.2	81.3	66
62	24	23.3	18		79	74.6	24
63	45	44.1	31		23.5	19.3	28
64	52.9	47.9	16		76.2	72.5	62
65	52.3	50.6	30		33	31.5	51
66	50.9	47.5	25		48.7	46.7	49
67	18.3	16.3	5		34	33.8	27
68	34.3	29.5	55		75.8	74	19
69	50.1	48.6	17		35.2	35	22
70	57.4	56.4	49		22.9	22.4	64
71	9.2	6.5	58		82.8	79.3	29
72	36.9	33.3	35		63.8	63.8	50
73	41.1	38.2	36		46.4	41.5	50
74	43.3	40.7	6		58.7	57.8	37
75	46.8	42.7	28		64	63.3	57
76	51.7	47	11		87.1	86.1	50
77	13.3	8.7	19		75	70.6	38
78	57.3	54.3	14		17	14.4	31
79	59.6	54.6	9		39.6	36.4	13
80	18.3	14.9	33		63.8	62.9	23
81	42.1	41	59		25.5	22.2	24
82	13.8	9.2	49		79.8	76.6	27
83	32.9	31.3	7		13.1	11.5	21
84	54	52.8	25		34.3	32.7	49
85	34.4	31.2	9		71.2	68.5	16
86	23.6	22.6	42		29.5	25.4	47
87	4.7	4	5		23.4	21.6	7
88	59	58.2	38		12.6	9.5	39
89	26.5	24.5	39		15.5	14	16
90	34.5	30.8	48		60	59.4	4
91	24.5	20.5	56		20.9	17.1	12
92	3.9	1.9	34		81.8	79.8	45
93	5	4.8	31		89	84.1	56
94	58.3	58.1	30		38.1	35	39
95	33.6	32.1	18		15.5	12.7	51
96	45.6	42.7	9		60.3	58.4	21
97	38.8	34.9	18		64.2	63.1	8
98	35.6	34.2	47		52.2	49.5	18
99	17	12	28		4.9	3.3	26
100	18	15.5	51		41.3	41.2	18
101	58.5	55.4	50		64.6	63.5	19
102	20.9	19.9	48		49.6	45.6	47
103	32.5	32.1	6		46.4	42.4	41
104	19	14.4	35		51.8	49	54
105	4.4	4	27		78.8	77.6	60
106	67.6	67.4	39		55.2	54.7	21
107	59.2	54.3	57		21	17.3	43
108	25	21.7	25		32.5	30.5	67
109	55.7	52.8	62		43.5	43	3
110	25.7	23.9	62		11.9	9.5	65
111	49.1	44.7	29		15.1	10.4	14
112	67.7	66.3	28		50.1	48.7	45
113	45	41	65		81.2	79.7	36
114	48.6	43.6	63		83.8	79.1	35
115	25.9	25.7	55		68	65.1	28
116	37.8	37	50		54.4	50.8	14
117	25.7	20.8	31		54.5	51.4	12
118	27.3	24.8	51		4.9	1.3	57
119	65	64.2	30		30.7	29	50
120	58.3	56.9	57		45	40.4	60
121	8.6	4.6	62		20.4	17.4	11
122	40	37	33		24	23.9	5
123	3.9	3	20		79.1	78.4	53
124	21.2	19.3	54		22.8	18.2	31
125	36	35.1	23		66	65.8	24
126	36.2	33.8	51		88.1	85.6	31
127	67.4	66.3	17		8.6	3.8	60
128	24	21	19		38.3	35.1	60
129	10	8.8	49		52.1	49.1	49
130	36.4	36.4	11		23.7	20.7	6
131	38.4	37.5	46		67.1	63.3	38
132	32.7	28	44		63.4	61.3	33
133	11.9	11	11		45.9	41	10
134	8.7	5.5	17		77.3	74.4	25
135	13.5	10.5	33		46.5	42.6	27
136	18.3	14.8	12		63.9	60	56
137	3.8	3	37		83.2	81.3	62
138	67.3	65.3	53		5.4	1.7	55
139	24.7	22.2	53		9	6.4	61
140	29	29	16		78.2	74.2	66
141	12.4	11.4	54		27.3	25.3	3
142	26.4	21.9	8		67	62.8	14
143	24.2	19.2	70		84.1	82.1	44
144	59	55	60		77.7	73.9	15
145	18.7	16.7	40		51.7	51.4	38
146	29.6	28.4	37		79	74.5	33
147	46.9	46.5	69		50	46.1	10
148	59.9	57.7	10		30.5	29.7	29
149	38.7	35.6	33		49.8	49.7	47
150	35.7	32.2	45		59.8	59.1	17
151	34.4	33.6	60		17.4	15.7	67
152	32	27.1	43		32.1	31.2	54
153	22.8	18.1	43		41.1	38.1	54
154	16.9	16.2	56		54.1	53.1	59
155	9	4.2	28		13.6	10.8	62
156	63.8	59.4	46		43	39.3	45
157	10.2	5.3	54		85.8	82.9	56
158	52.8	51.8	48		35.6	32.6	53
159	42.1	39.6	22		25	22.7	9
160	9.6	7.2	58		8.8	4.4	50
161	17.8	14.2	59		41.8	39.5	26
162	48	46.3	30		20.4	19.4	23
163	67.3	63	11		60.3	59	22
164	29	25	65		68	64.5	68
165	13.9	11.3	49		65	61.3	66
166	18.2	16.1	35		11.3	9	4
167	54.9	53.5	67		37.5	32.9	22
168	78.8	76.5	67		88.3	87.7	30
169	10.5	8.4	17		62.8	58.2	28
170	21.7	17.8	24		71.8	69.2	59
171	7.9	7.1	29		86.5	84.6	53
172	25.1	23.8	34		71.8	67.3	46
173	22.4	17.5	23		47.1	45.2	65
174	62.8	58.3	18		89.3	85.7	11
175	73.1	68.3	8		75	70.1	28
176	21.1	20.7	18		69.6	66.8	11
177	50.8	46.4	41		87.4	83.5	16
178	18.5	18.4	43		24.7	22.6	15
179	41	36.7	11		73.9	72.6	14
180	56.9	53.6	50		80.6	79.1	15
181	60.5	60.3	13		89.1	87	56
182	56.9	55.1	42		55	54.3	71
183	20	17	13		24.7	22.4	57
184	19.5	18.2	5		4.8	2.3	39
185	25.5	20.9	53		84.2	81.8	14
186	50.4	50	15		86.9	83.5	19
187	73.1	70.8	41		85.7	81	39
188	18.5	15.7	54		40.8	38.9	51
189	71.3	66.4	4		57.2	53.5	56
190	69	66.9	26		6.5	5.5	41
191	60.8	57.8	15		79.1	76.1	29
192	19.7	18.7	13		14.6	12.2	1
193	21.9	19	1		1.1	0.8	2
194	9.4	8.6	2		5	4	14
195	34.9	32.6	5		8	4.9	30
196	21.9	21.3	13		27	22	18
197	27.4	23.3	12		14.8	11.9	11
198	14.3	11.7	1		54.4	53.6	15
199	5.2	3.8	3		89.5	87.1	100
200	14.3	10.9	7		11.5	7.6	14