Question 924119
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Hi
 This is the right set-up: mean(x)-/+ z*(standard deviation/sqrt(n))
mean = 2100, sd = 100
I. try z = 2.576 0r (2.58)
2100 ± 47 rounded (Do know what rounding is preferred)
CI: ( 2053, 2147)  (Use Format desired for CI)
0r
II. Possibly they are looking for the t-value to be used(DF = 29): t = 2.76
2100 ± 50
....Small Sample t-values
DF	Probability, p 2-tailed			
	0.1	0.05	0.01	0.001
1	6.31	12.71	63.66	636.62
2	2.92	4.3	9.93	31.6
3	2.35	3.18	5.84	12.92
4	2.13	2.78	4.6	8.61
5	2.02	2.57	4.03	6.87
6	1.94	2.45	3.71	5.96
7	1.89	2.37	3.5	5.41
8	1.86	2.31	3.36	5.04
9	1.83	2.26	3.25	4.78
10	1.81	2.23	3.17	4.59
11	1.8	2.2	3.11	4.44
12	1.78	2.18	3.06	4.32
13	1.77	2.16	3.01	4.22
14	1.76	2.14	2.98	4.14
15	1.75	2.13	2.95	4.07
16	1.75	2.12	2.92	4.02
17	1.74	2.11	2.9	3.97
18	1.73	2.1	2.88	3.92
19	1.73	2.09	2.86	3.88
20	1.72	2.09	2.85	3.85
21	1.72	2.08	2.83	3.82
22	1.72	2.07	2.82	3.79
23	1.71	2.07	2.82	3.77
24	1.71	2.06	2.8	3.75
25	1.71	2.06	2.79	3.73
26	1.71	2.06	2.78	3.71
27	1.7	2.05	2.77	3.69
28	1.7	2.05	2.76	3.67
29	1.7	2.05	2.76	3.66
30	1.7	2.04	2.75	3.65