Question

Петя прочитал книгу за три недели. В 1 неделю он прочитал 25% всей книги, во 2 неделю 35% книги, а в 3 неделю оставшиеся 200 страниц. Сколько страниц было в книге?

Answer 1

1. 25+35=60 процентов - прочитал Петя за первые две недели
2. 100-60=40 процентов - осталось прочитать. 
Следовательно, 200 страниц составляют 40 процентов. 
3. 200*100:40=500 страниц - составляют 100 процентов
Ответ: 500 страниц

Answer 2

Calculation of the Total Number of Pages in the Book

To determine the total number of pages in the book, we can use the information provided about the percentage of the book read in each week and the remaining 200 pages in the third week.

Let's denote the total number of pages in the book as x.

According to the given information: - In the first week, Petya read 25% of the entire book, which is equal to 0.25x pages. - In the second week, Petya read 35% of the book, which is equal to 0.35x pages. - In the third week, Petya read the remaining 200 pages.

To find the total number of pages in the book, we can set up the following equation:

0.25x + 0.35x + 200 = x

Simplifying the equation:

0.6x + 200 = x

Subtracting 0.6x from both sides:

200 = 0.4x

Dividing both sides by 0.4:

x = 500

Therefore, the total number of pages in the book is 500.