Question

The margin of error for a confidence interval depends on the confidence level, the standard deviation, and the sample size. Fix the confidence level at 95% and the sample standard deviation at 1 to examine the effect of the sample size. Find the margin of error for sample sizes of 5 to 100 by 5's -- that is, let n = 5, 10, 15, ..., 100. (Round your answers to three decimal places.)

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

Answer 1

Sample size(n)	t=using command"=tinv(0.05,n-1)	standard error error=sd/n^1/2	margin of error=t*std error
5	2.776	0.447	1.242
10	2.262	0.316	0.715
15	2.145	0.258	0.554
20	2.093	0.224	0.468
25	2.064	0.2	0.413
30	2.045	0.183	0.373
35	2.032	0.169	0.344
40	2.023	0.158	0.32
45	2.015	0.149	0.3
50	2.01	0.141	0.284
55	2.005	0.135	0.27
60	2.001	0.129	0.258
65	1.998	0.124	0.248
70	1.995	0.12	0.238
75	1.993	0.115	0.23
80	1.99	0.112	0.223
85	1.989	0.108	0.216
90	1.987	0.105	0.209
95	1.986	0.103	0.204
100	1.984	0.1	0.198