Question 1173020
  <pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi, ME ={{{ z*sigma/sqrt(n)}}}
c=.90​,X=12.3, S=4.0, n=6
DF = 6-1 = 5 , First column:  z = 2.015
0.1 0.05 0.02 0.01
2  2.9200  4.3026  6.9646  9.9247  14.0887  
3  2.3534  3.1824  4.5407  5.8408  7.4534  
4  2.1319  2.7764  3.7470  4.6041  5.5976 
5  2.0150  2.5706  3.3650  4.0322  4.7734  
6  1.9432  2.4469  3.1426  3.7074  4.3168  
ME ={{{ 2.015*4/sqrt(6)}}} = 3.29
12.3 - 3.29 < {{{mu}}} < 12.3 + 3.29
  9.01 < {{{mu}}} < 15.59
    9.0 < {{{mu}}} < 15.6
Generally: Round the confidence interval limits to the same number of decimal places as the sample standard deviation