Предмет: Математика, автор: allaletenko

Склади короткий запис задачі

У бібліотеку привезли 400 нових книг. Підручники становили усіх книг. Книги з оповіданнями становили усіх книг. На скільки більше привезли підручників, ніж книг з оповіданнями?

Ответы

Автор ответа: kukusmika
1

Ответ:

За умовою задачі, підручники становлять деяку частину усіх книг, а книги з оповіданнями становлять іншу частину. Оскільки сума частин дорівнює 1 (усі книги), то можна записати дві рівності:

Підручники / Усі книги = частка підручників

Книги з оповіданнями / Усі книги = частка книг з оповіданнями

Нехай частка підручників дорівнює х. Оскільки сума часток дорівнює 1, то частка книг з оповіданнями дорівнює (1 - х).

Тоді кількість підручників становить 400 * х, а кількість книг з оповіданнями становить 400 * (1 - х).

Щоб знайти на скільки більше привезли підручників, ніж книг з оповіданнями, потрібно порівняти ці кількості:

400 * х - 400 * (1 - х) = 400 * (2 * х - 1)

Отже, відповідь: на скільки більше привезли підручників, ніж книг з оповіданнями, залежить від значення х і дорівнює 400 * (2 * х - 1). Якщо, наприклад, підручники становлять 60% усіх книг, то на скільки більше привезли підручників, ніж книг з оповіданнями, дорівнює 400 * (2 * 0.6 - 1) = 80. Отже, привезли на 80 підручників більше, ніж книг з оповіданнями.

Пошаговое объяснение:

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