Demonstrated is how the concept of equivalence classes modulo n can provide a basis for solving a wide range of problems. Five problems are presented and described to illustrate the power and usefulness of modular arithmetic in problem solving. (MNS)

Four different types of problems from graph theory are presented and discussed. (MK)

Provides an activity as an example of how matrices can be introduced from finite graphs and how finite graphs can be analyzed by examining their matrix representations. Presents the materials, objectives, prerequisites, directions, extension activities, answers, and worksheets. (YP)

Discusses figurate number learning activities using patterns and manipulative models. Provides examples of square numbers, triangular numbers, pentagonal numbers, hexagonal numbers, and oblong numbers. (YP)

Provides a discussion and an example of a problem which occurs in mathematical contests or entrance examinations and deals with the question of the magnitude of exponentials. Includes additional illustrative examples. (RT)

Determines which chessboards contain a chromatic rectangle having all four corners the same color for any black-white coloring. Expands the problem to a three color problem. (YP)

Describes a take-home exam story problem based on stoichiometry. Requires the student to determine the percentage of phosphoric acid in a large container of nitric acid if a man fell into it. Provides assumptions, clues, and an acceptable solution. (MVL)

Discusses making tessellations by using a polyomino. Illustrates the various ways for various shapes of polyomino. Provides several diagrams and instructional guides. (YP)