Answer: (0.829, 0.903)
Step-by-step explanation:
We know that [tex]a\pm b=(a-b,\ a+b)[/tex] (1)
The given confidence interval : 0.866 ± 0.037
To express the given confidence interval in open interval form , we split the given expression as :
[tex]0.866 \pm 0.037 \\\\=(0.866-0.037,\ 0.866+0.037)\ \ \text{[By using (1)]}\\\\=(0.829,\ 0.903)[/tex]
Therefore, the confidence interval in open interval form would be (0.829, 0.903) .