In this problem, assume that the distribution of differences is approximately normal. Note : For degrees of freedom d.f. not in the Student's t -table, use the closest d.f. that is smaller . In some...

In this problem, assume that the distribution of differences is approximately normal.Note: For degrees of freedom d.f. not in the Student'st-table, use the closest d.f. that issmaller. In some situations, this choice of d.f. may increase theP-value by a small amount and therefore produce a slightly more "conservative" answer.

In environmental studies, sex ratios are of great importance. Wolf society, packs, and ecology have been studied extensively at different locations in the U.S. and foreign countries. Sex ratios for eight study sites in northern Europe are shown below.