Question

В библиотеке на одной полке стояло 33 книги,а на другой-40 книг. из них детям выдали 20 книг, сколь книг осталось на этих полках? реши задачу разными способами

Answer 1

1 способ:
1)33-20=13(кн.)- осталось на первой полке
2)40+13=53(кн.)- осталось всего
2 способ:
1)40-20=20(кн.)- осталось на второй полке
2)20+33= 53(кн.)- осталось всего
3 способ:
1)40+33=73(кн.)- было всего
2) 73-20=53(кн.)- осталось всего
Ответ: осталось 53 книги.

Answer 2

Problem Analysis

We are given that there are 33 books on one shelf and 40 books on another shelf. Out of these books, 20 were given to children. We need to determine how many books are left on the shelves.

Solution 1: Subtraction

We can solve this problem by subtracting the number of books given to children from the total number of books on each shelf.

On the first shelf, there were 33 books. Out of these, 20 were given to children. Therefore, the number of books left on the first shelf is 33 - 20 = 13.

On the second shelf, there were 40 books. Out of these, 20 were given to children. Therefore, the number of books left on the second shelf is 40 - 20 = 20.

So, there are 13 books left on the first shelf and 20 books left on the second shelf.

Solution 2: Addition and Subtraction

Another way to solve this problem is by adding the number of books on both shelves and then subtracting the number of books given to children.

The total number of books on both shelves is 33 + 40 = 73.

Out of these, 20 books were given to children. Therefore, the number of books left on both shelves is 73 - 20 = 53.

Since we don't know the distribution of books between the two shelves, we cannot determine the exact number of books left on each shelf individually using this method.

Conclusion

Using the first method, we determined that there are 13 books left on the first shelf and 20 books left on the second shelf. Using the second method, we determined that there are 53 books left on both shelves combined.