Question

Книга дороже тетради на 80 руб.За книгу и тетрадь заплатили 120 руб.Сколько нужно заплатить за 5 таких тетрадей и 3 такие книги?

Answer 1

За книгу 240р
за тетрадь 200р
Вместе:200+240=440

Answer 2

1) 120-80=40(р)
2)40*5=200(р)
3)80*3=240(р)
4)200+240=440(р)
Ответ: заплатили за 3 такие книги и 5 таких тетрадей заплатили 440 рублей.
Можно укротить и сделать в 2 действия если соединить эжти решения в одно)

Answer 3

Problem Analysis

We are given that a book is 80 rubles more expensive than a notebook. The total cost of a book and a notebook is 120 rubles. We need to find the total cost of 5 notebooks and 3 books.

Solution

Let's assume the cost of a notebook is x rubles. Since the book is 80 rubles more expensive than the notebook, the cost of the book is x + 80 rubles.

According to the given information, the total cost of a book and a notebook is 120 rubles. So we can write the equation:

x + (x + 80) = 120

Simplifying the equation, we get:

2x + 80 = 120

Subtracting 80 from both sides, we have:

2x = 40

Dividing both sides by 2, we get:

x = 20

So the cost of a notebook is 20 rubles, and the cost of a book is 20 + 80 = 100 rubles.

To find the total cost of 5 notebooks, we multiply the cost of one notebook by 5:

Total cost of 5 notebooks = 20 * 5 = 100 rubles

To find the total cost of 3 books, we multiply the cost of one book by 3:

Total cost of 3 books = 100 * 3 = 300 rubles

Therefore, the total cost of 5 notebooks and 3 books is 100 + 300 = 400 rubles.

Answer

The total cost of 5 notebooks and 3 books is 400 rubles.