The worksheet includes transparent codes and maplets with nice interactive plots for three typical models used in the inferential statistics: Standard Normal, Student's t, and Chi-square. Each of the maplets performs the following two tasks: 1. Given a cut-off value (z-value, t-value, or chi-squared ) find the area under the appropriate probability density plot to the LEFT of the cut-off value, and 2. Given an area, find the corresponding cut-off value. The worksheet can be used as: Simple tool replacing obsolete statistical tables or "black box" types of software products in teaching introductory statistics courses. Demonstration of some of the Calculus tools in action in the field of statistics. Demo of certain document tools and techniques of Maple 10 or 11 (point-and-click technique, authoring maplets, embedded elements, autoexecution).