The Great International Math On Keys Book, by Ralph A. Oliva, M. Dean LaMont, and Linda R. Fowler
The year was 1976. Texas Instruments had created hand calculators like the TI-30 and SR-40 Electronic Slide Rule Calculators, but faced a populace that had grown comfortable using its slide rules  and needed to be convinced of the benefits of using an electronic calculator. How was this new technology to be sold? Enter a group of writers working on behalf of Texas Instruments with the goal of selling the technology but presenting their work as an educational work. It may seem difficult to believe in our contemporary age that it would be necessary to sell the educational and entertainment purposes of calculators, and that calculators would be seen as an aid to better understanding fundamental aspects of mathematics, but so it was in the mid-1970’s, and this book is evidence of the immense effort and creativity that went into promoting the use of calculators as a way of improving one’s mathematical knowledge. To be sure, the book is of advanced enough mathematics that many high school students would be hard pressed to understand all of the mathematics involved, and many adults who have not focused on the subject matter of mathematics would be seriously hard-pressed to understand the approach of the authors or feel themselves up to the demanding rigors of framing problems correctly, but for those writers who do enjoy math , this book is a glimpse into the makings of a revolution in the approach to calculators and gives insight into the time when slide rules went from standard tools of engineering and related fields to a curiosity relegated to the collections of antiquarians like myself.
What kind of mathematics did these authors speaking on behalf of Texas Instruments promote for their early handheld calculator and expect their reading audience to find worthy of interest? The book is divided into nine chapters. After a short introduction, the authors show the basic keys on the TI-30 calculator. After this the authors encourage readers to key up conversions between English and metric measurements. After this the authors discuss the use of calculators as an aid to home management in tasks like balancing a checkbook, diet planning, and recipe conversions, along with calculating mortgage and interest payments. After this the authors spend some time showing how a calculator can unlock algebra by solving linear equations, using the distance formula, dealing with the Pythagorean equation, and using the quadratic formula. After this there is a short chapter on business finance that involves currency calculations as well as compound interest and depreciation. A chapter on trigonometry follows with a discussion of sines, cosines, limits, and vectors, before the authors write a chapter on probability and statistics that examines the probabilities of d6 as well as permutations and ombinations, factorials, average and median, as well as standard deviation. The main part of the book closes with chapters on how the calculator can be of use in solving problems of physics and chemistry as well as puzzles and games before containing an appendix on conversion charts to aid in calculation, a bibliography for further reading, and an index of materials. The result is a book that is impressive in its scope as well as its respect for the mathematical literacy of its audience.
This is not a book to be taken lightly, nor is it a book that condescends to its audience. A shrewd reader of this book will see that there are clearly sales purposes in mind with the book, as the authors assume a familiarity among the readers in manipulating equations to understand the proper order or to use various means to eliminate unknowns and simplify equations. In order to use this book effectively a reader would need to have a firm understanding of algebra, including linear algebra, and some familiarity with probability and statistics as well as finance, geometry, and trigonometry. Likewise, the book has a certain sense of humor and even manages to show some drawings that combine a sense of humor as well a sound knowledge of the visualization of math problems. This is a rare book of its kind in that it shows a great attention to education and not only to marketing. It would be rare to find such an informational approach to marketing in contemporary business, and so this book is an example of the sort of business practices we could have as a society if our companies valued intelligent customers who were able to recognize a positive change when they saw it and adopt new technologies not simply to make money for a company but because those technologies legitimately made their lives better. Imagine that.
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