A magnetic set of 32 circle sectors with triple marking for demonstrating fractions, their comparison and operations with them in mathematics lessons in grades 5 and 6.
This set of circle sectors shows how a whole is divided into equal parts, how common fractions are formed and written, compared and used in operations, and how a fraction is converted into a decimal fraction and a percentage. It is used in mathematics lessons in grades 5 and 6 when studying parts of a whole, fractions and operations with them, percentages and the construction of pie charts.
The circle has a diameter of 210 mm, and all sectors share the same radius. The set covers the denominations 1/2, 1/3, 1/4, 1/5, 1/6 and 1/12, with central angles of 180, 120, 90, 72, 60 and 30 degrees respectively, and contains 32 sectors in total. Every sector carries a triple marking – the common fraction, the decimal fraction and the percentage value – and each denomination has its own colour. The sectors are made of dense plastic and each part of the set is fitted with a magnetic base, so the model works on a magnetic (metal) board or on a table. The product needs no power supply and is intended for frontal demonstration to the class on the board.
The set includes sectors 1/2 – 2 pcs, sectors 1/3 – 3 pcs, sectors 1/4 – 4 pcs, sectors 1/5 – 5 pcs, sectors 1/6 – 6 pcs and sectors 1/12 – 12 pcs, giving 32 sectors in total; a passport with a warranty card – 1 pc; and individual transport packaging – 1 pc. The product requires no assembly before first use.
Sectors of one denomination form a full circle, which lets the class compare parts by overlaying one sector on another, check equivalent fractions and find a common denominator. Because every part carries a magnet, keep the sectors 10 cm away from bank cards, magnetic media and mechanical watches and 30 cm away from pacemakers and other implanted medical devices. Clean the sectors with a soft dry or slightly damp cloth without solvents, alcohol, acetone or abrasives, and store them flat in the original packaging at a temperature from +5 to +40 degrees Celsius and a relative humidity of 80 percent without condensation. The service life is 5 years and the warranty period is 12 months from the date of sale.
