Вопрос школьника по предмету Математика
Очень простая задача!
Сколько существует трехзначных чисел, которые при зачеркивании средней цифры уменьшаются в 10 раз?
Нужно обязательно решение!
Ответ учителя по предмету Математика
Ответ такой: Существует только девять чисел, которые при зачеркивании уменьшается в десять раз — 100, 200, 300, 400, 500, 600, 700, 800, 900
Доказательство: И так, число 164, вычеркиваем 6, ответ получается
14, а 10/164 это — 16,4, но никак не 14. А вот число 100 (как пример), при вычеркивании нуля превращется в 10, а как известно 10/100 это 10.
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