Question

На двух книжных полках находилось 72 книги. После того как с одной полки переложили на другую 15 книг, на второй полке оказалось на две книги больше, чем н а первой полке. Сколько книг было на каждой полке первоначально?

Answer 1

Х книг на одной
72-х на другой
х-15 стало на одной
72-х+15=87-х стало на другой
х-15+2=87-х
2х=87+15-2
2х=100
х=50 книг на одной
72-50=22 книги на другой

Answer 2

Problem Analysis

We are given that there are 72 books on two bookshelves. After transferring 15 books from one shelf to the other, the second shelf has two more books than the first shelf. We need to determine the number of books on each shelf initially.

Solution

Let's assume that there were x books on the first shelf initially. Since the second shelf had two more books than the first shelf after the transfer, there were x + 2 books on the second shelf initially.

After transferring 15 books from the first shelf to the second shelf, the first shelf would have x - 15 books, and the second shelf would have (x + 2) + 15 books.

According to the problem, the total number of books on both shelves is 72. Therefore, we can set up the following equation:

(x - 15) + [(x + 2) + 15] = 72

Simplifying the equation:

2x + 2 = 72

2x = 70

x = 35

So, there were initially 35 books on the first shelf and 35 + 2 = 37 books on the second shelf.

Answer

There were initially 35 books on the first shelf and 37 books on the second shelf.