Assume that we want to construct a confidence interval. Do one
of the following, as appropriate: (a) find the critical
value tα/2,
(b) find the critical value zα/2, or (c) state
that neither the normal distribution nor the t distribution
applies.
Here are summary statistics for randomly selected weights of
newborn girls:
N =180, x = 33.5 hg, S =7.8 hg.
The confidence level is 99%.
Select the correct choice below and, if necessary,
fill in the answer box to complete your choice.
(A) tα/2= -----------
(B) zα/2 = -----------