A large buyer of household batteries wants to decide which of two equally priced brands to purchase. The buyer takes a random sample of 100 batteries of each brand. The lifetimes, measured in hours, of the batteries, are recorded in the Batteries worksheet file. Before testing for the differences between the mean lifetimes of these two batteries, he must first determine whether the underlying populations' variances are equal.

• He also needs to verify the data with a test for equal population variances. He needs to interpret the results for management.
• And based on the test for equal population variances, he needs to decide which type of test should be used to determine if a difference exists in the population means, then perform this test and interpret the results.

Batteries Data
Battery Brand 1	Brand 1 Lifetime	Battery Brand 2	Brand 2 Lifetime
1	99.11	1	110.65
2	99.45	2	92.24
3	98.39	3	96.63
4	97.07	4	99.45
5	99.97	5	102.55
6	100.06	6	109.60
7	98.20	7	96.53
8	98.13	8	104.64
9	107.73	9	88.03
10	95.58	10	96.87
11	96.98	11	96.02
12	100.47	12	97.33
13	101.23	13	105.14
14	100.39	14	99.86
15	106.07	15	93.81
16	98.02	16	92.26
17	100.26	17	103.67
18	102.48	18	93.61
19	97.88	19	97.28
20	102.58	20	102.51
21	101.00	21	106.59
22	97.01	22	100.90
23	103.91	23	98.67
24	96.23	24	102.64
25	99.84	25	99.76
26	102.49	26	108.11
27	97.80	27	101.96
28	101.10	28	98.36
29	99.51	29	101.93
30	99.49	30	112.25
31	101.63	31	105.35
32	104.85	32	100.95
33	99.69	33	85.00
34	97.68	34	95.50
35	100.31	35	111.24
36	95.29	36	109.34
37	101.00	37	99.67
38	92.23	38	101.57
39	99.87	39	105.21
40	98.70	40	92.84
41	97.70	41	99.89
42	102.67	42	94.24
43	100.30	43	96.43
44	101.76	44	93.64
45	100.11	45	97.44
46	103.05	46	109.93
47	100.82	47	100.20
48	99.94	48	101.34
49	98.89	49	97.41
50	95.22	50	109.89
51	99.55	51	107.33
52	102.67	52	95.24
53	98.43	53	91.33
54	101.69	54	102.49
55	100.86	55	106.89
56	98.86	56	103.68
57	99.19	57	103.97
58	95.90	58	93.47
59	101.85	59	94.93
60	96.05	60	101.94
61	103.36	61	98.81
62	102.31	62	103.66
63	103.15	63	102.03
64	102.03	64	99.62
65	99.00	65	100.96
66	101.36	66	99.05
67	98.75	67	95.72
68	99.03	68	90.28
69	98.75	69	88.87
70	94.80	70	110.15
71	101.26	71	113.99
72	99.08	72	97.37
73	103.60	73	102.17
74	102.56	74	95.82
75	95.44	75	104.44
76	98.26	76	108.21
77	95.05	77	100.28
78	100.65	78	92.43
79	99.86	79	91.92
80	105.21	80	81.47
81	101.26	81	92.58
82	103.88	82	106.49
83	106.71	83	102.46
84	100.07	84	92.72
85	99.30	85	101.97
86	103.74	86	96.85
87	99.60	87	96.92
88	104.24	88	103.56
89	100.59	89	87.85
90	101.17	90	100.65
91	96.65	91	96.33
92	100.27	92	89.44
93	98.99	93	103.91
94	103.24	94	103.96
95	100.29	95	87.99
96	93.25	96	98.86
97	102.86	97	96.47
98	102.65	98	101.32
99	102.74	99	103.46
100	98.78	100	96.70