20-15=5(ц)
80+10=90(руб)
90/5=18(руб)-1 ц ржи
20*18-10=350 рублей
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1. Математическое выражение, стоящее под
знаком обыкновенной дроби.
2. Как на Руси называли дроби?
3. Кто впервые в Европе ввёл десятичные
дроби?
4. Математическое выражение, стоящее над
знаком обыкновенной дроби.
5. Формат дроби.
6. В какой стране впервые
встречаются десятичные дроби?
7. Как называется эта дробь 9/8
?
8. Формат дроби.
9. Греческий математик, который
ввёл слова «числитель» и «знаменатель» в оборот?
10. Число, состоящее из одной или
несколько частей (долей) единицы?
Средним арифметическим нескольких чисел называют частное от деления суммы этих чисел на число слагаемых.
А) Площадь прямоугольника равна произведению длины на ширину. 500*380=190000 кв.м. В 1 гектаре 10 000 кв. м. Площадь прямоугольника равна 19 га.