If a second study yielded the same sample statistic values, but were done with 100 women, what would happen to the width of the 95% confidence interval? Well, we know since this sample is smaller than the previous example, the SEM will be larger, leading to a wider confidence interval. In non-mathematical terms, our sample contains less information than a sample of 200 women, and therefore will yield a less precise (more uncertain) estimate of the population mean. The proof is as follows: X+2*(SEM), where SEM = SD 25 Vn V100 = 2.5 mm Hg Plugging in our sample values gives us: 140 +2*(2.5) > (135 mm Hg, 145 mm Hg) H : /