Question

Ученики помогали школьной библиотеки переплетать книги. В первый день они переплели 2/7 всех книг, во второй день- 1/3 всех книг, а в третий день- остальные 40 книг. Сколько всего книг переплели ученики за три дня?

Answer 1

1) 2/7 + 1/3 = 6/21 + 7/21 = 13/21 (части) всех книг переплели за 2дня
2) Все книги принимаем за 1 (единицу)
   1 - 13/21 = 8/21(части) книг составляют 40 оставшихся книг
3) 40 : 8/21 = 40 : 8 * 21 = 105(книг)
Ответ: 105 книг школьники переплели за 3 дня.

Answer 2

Calculation of the Number of Books Bound by Students

To calculate the total number of books bound by the students over three days, we need to add up the number of books bound each day.

On the first day, the students bound 2/7 of all the books. On the second day, they bound 1/3 of the remaining books. On the third day, they bound the remaining 40 books.

Let's calculate the total number of books bound step by step:

1. Calculate the number of books bound on the first day: - The students bound 2/7 of all the books.

2. Calculate the number of books remaining after the first day: - Since the students bound 2/7 of all the books on the first day, there are 5/7 of the books remaining.

3. Calculate the number of books bound on the second day: - The students bound 1/3 of the remaining books. - Multiply the remaining books by 1/3 to find the number of books bound on the second day.

4. Calculate the number of books remaining after the second day: - Subtract the number of books bound on the second day from the remaining books after the first day.

5. Calculate the number of books bound on the third day: - The students bound the remaining 40 books.

6. Calculate the total number of books bound over three days: - Add up the number of books bound on each day.

Let's perform the calculations:

1. Number of books bound on the first day: 2/7 of all the books. 2. Number of books remaining after the first day: 5/7 of all the books. 3. Number of books bound on the second day: 1/3 of the remaining books. 4. Number of books remaining after the second day: Remaining books after the first day minus books bound on the second day. 5. Number of books bound on the third day: 40 books. 6. Total number of books bound over three days: Sum of the books bound on each day.

Please wait a moment while I perform the calculations.