PUZZLE FOR ENTERTAINING ARITHMETIC Russian patent published in 1996 - IPC

FIELD: puzzles. SUBSTANCE: device has housing bottom and housing cover. Game fields and limiting flanges are located on outer facets of bottom and cover of housing. In addition device has game tokens having labels of digits from 1 to 8 or 9. according to second claim in invention specification additional game tokens having signs of arithmetic operations are added. Goal of player is fastest search of solution using four arithmetic operations (addition, subtraction, multiplication and division) for arbitrary game tokens. EFFECT: possibility to develop mathematical thinking for children and to entertain adults. 2 cl, 4 dwg, 3 tbl