Discusses three types of bridges to determine how best to model each one: (1) drawbridge; (2) balance bridge; and (3) bascule bridge. Describes four experiments with assumptions, analyses, interpretations, and validations. Provides several diagrams and pictures of the bridges, and typical data. (YP)

Presents three teaching ideas: (1) investigating patterns in the sum of four numbers in a square array, no two from the same column or row; (2) using three-dimensional coordinates to generate models of three tetrahedra; and (3) applying the K=rs area formula for a triangle to other polygons. (MDH)

Presents two methods of calculating the expected value for a participant on the television game show "The Wheel of Fortune." The first approach involves the use of basic expected-value principles. The second approach uses those principles in addition to infinite geometric series. (MDH)

Compares the methods of calculating the transfer rates of students transferring from community colleges to senior institutions developed by the Center for the Study of Community Colleges and the National Effectiveness Transfer Consortium. Indicates that neither of the models considers program of study and only one considers student intent. (12…

A new optometry-oriented program for the Macintosh computer has been written for the Neural Sciences Computer-Assisted Learning Package to include graphics and synthesized speech. It has 21 modules in 6 categories: anatomical drawings; diagrams illustrating physiological concepts; records from experiments; flow charts of neuroanatomical pathways;…

Great care must be taken when making the jump from the finite to the infinite. The concept of infinity is explored through a series of examples from infinite sequences, presenting potential contradictions that could occur from a natural extension of finding the fraction form of a repeating decimal. (MDH)

Presents the problem of finding the maximum area of a quadrilateral when three of the four sides are given. Incorporates several parts of the secondary school precalculus curriculum into the solution. Develops the formula to solve the problem. (MDH)

Examines the problem of determining the minimum center of mass for a can with a varying height of liquid in it. Uses PC SOLVE computer software to graphically represent the problem situation. (MDH)

Proposes lessons for algebra students using the context of tax calculations to learn about the concepts of slope, split functions, averages, rates, marginal rates, and percents. Students explore ramifications of possible tax revisions. (MDH)

Described is an activity that categorizes a two-digit number as "sneaky" if the continued process of taking the difference of the squares of its digits leads to a difference of zero. Other categorizations are determined by whether the difference process ends in a one-digit number or continues in a loop of numbers. (MDH)

Describes an approximate document ranking process that uses a compact array of in-memory, low-precision approximations for document length. Combined with another rule for reducing the memory required by partial similarity accumulators, the approximation heuristic allows the ranking of large document collections using less than one byte of memory…

Presents a mathematical problem that, when examined and generalized, develops the relationships between power and efficiency in energy transfer. Offers four examples of simple electrical and mechanical systems to illustrate the principle that maximum power occurs at 50 percent efficiency. (MDH)

Outlines a model for determining library collection use, incorporating prediction of future demand and cost analysis to assist collection development librarians determine whether weeding or remote storage is the most economically feasible way to address the space problem in libraries. (13 references) (EA)

Describes research that was conducted to determine the search state patterns through which users retrieve information in hypertext systems. Use of the Markov model to describe users' search behavior is discussed, and search patterns of different user groups were studied by comparing transition probability matrices. (Contains 25 references.) (LRW)

Emphasizes a real-world-problem situation using sine law and cosine law. Angles of elevation from two tracking stations located in the plane of the equator determine height of a satellite. Calculators or computers can be used. (LDR)