Now the method we just went through is fine for z values of 1, 2, and 3. But what if the value of the z score is not a whole number like 2 but is instead 1.23 or −2.01? We need to find a way to be more precise. How do we do that? Simple—learn calculus and apply it to the curve to compute the area underneath it at almost every possible point along the x-axis, or (and we like this alternative much more) use Table B.1 found in Appendix B (the normal distribution table). This is a listing of all the values (except the very most extreme) for the areas under a curve that correspond to different z
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