Calculating ever faster
Throughout history, calculating better and faster has been an imperative, at the root of important stakes. Methods have multiplied, sometimes in surprising ways. Thus, Descartes used geometry to perform arithmetic operations! Mental calculation, with its tricks, has taken an important place in the teaching of mathematics, even if its approach has been revolutionized by the arrival of computers and calculators. The latter continue to adapt to integrate technological advances and remain essential pedagogical tools. Knowing how to calculate well remains indeed an imperative for good integration into society.
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Mental arithmetic: a vital skill | Tangente
There is unanimous agreement: mental arithmetic is fundamental both to mathematics education and to citizens of tomorrow. What lies behind this remarkable consensus, and where does mental arithmetic stand in schools today? Let's take stock.
Geometric “tricks” for arithmetic
The human mind often needs concrete representations of abstract concepts. Geometry can thus serve as an aid to calculation, as Descartes was among the first to show.
The magic of domino divisibility tests
You know the divisibility tests for 2, 3, 4, 5, 10, 20… and perhaps others as well. But are you familiar with "domino tests"? Variants of a famous divisibility test for 11, they make for a wonderful mathematical playground!
The mechanics of calculation
To calculate faster and more accurately, humans created devices as ingenious as they were varied! It can be hard to imagine that, only a few centuries ago, machines were expensive and cumbersome. Sophisticated calculations were therefore the preserve of an elite.
Fast calculation with the Trachtenberg method | Tangente
You may have heard of the "Trachtenberg method" in the recently released film Mary. It is an iterative method for performing impressive mental calculations with large numbers.
Learn to calculate with a calculator | Tangente
Machines generally calculate faster than people. But exactly how does a machine perform a simple addition? Revisiting the methods taught to children reveals two main techniques, which we can compare using CASIO's Graph 90+E calculator.
Numeracy: an asset for life | Tangente
Being able to estimate large numbers, calculate a proportion, understand a percentage, convert currencies, or simply perform basic arithmetic without the help of a smartphone or calculator is essential in everyday life. Yet innumeracy is on the rise.
Calculators in entrance exams: end of an era | Tangente
For several years now, some written papers in the competitive entrance examinations for France's engineering grandes écoles have prohibited calculators. But this was not a blanket rule.
An innovative new kind of calculator | Tangente
The French company Numworks has joined the select club of calculator manufacturers. This new machine is based on open-source principles.
Soroban and Japanese human calculators | Tangente
Practising the Japanese abacus is considered an art in Japan, where, as in judo, practitioners progress through kyu belt ranks and then dan grades.