Question

Лена прочитала книгу за 3 дня.В первый день она прочитала 20% всей книги,во второй - 5 остатка,а за третий день-последние 24 страницы .сколько стр в книге? 8

Answer 1

Х - всего страниц в книге
20% - это 20/100=0,2х - прочитано в 1-ый день
5/8 остатка - это (1-0,2)х*5/8=0,8х*5/8=8/10*5/8 х=5/10 х=0,5х
0,2х+0,5х+24=х
0,7х-х=-24
-0,3х=-24
х=80стр. - всего в книге

Answer 2

Calculation of the Total Number of Pages in the Book

To calculate the total number of pages in the book, we need to determine the number of pages read by Lena on each day and then add them together.

1. On the first day, Lena read 20% of the entire book. 2. On the second day, she read 5 pages less than the remaining pages. 3. On the third day, she read the last 24 pages of the book.

Let's calculate the number of pages read on each day and then add them together to find the total number of pages in the book.

1. First day: Lena read 20% of the book. - Let's assume the total number of pages in the book is x. - Therefore, Lena read 0.2x pages on the first day.

2. Second day: Lena read 5 pages less than the remaining pages. - After the first day, there are (1 - 0.2)x = 0.8x pages remaining. - Lena read 5 pages less than the remaining pages, so she read 0.8x - 5 pages on the second day.

3. Third day: Lena read the last 24 pages of the book. - After the second day, there are (0.8x - 5) - 24 pages remaining. - Lena read the last 24 pages on the third day.

To find the total number of pages in the book, we need to add up the number of pages read on each day:

0.2x + (0.8x - 5) + 24 = x

Now, let's solve this equation to find the value of x, which represents the total number of pages in the book.

Solving the Equation

To solve the equation 0.2x + (0.8x - 5) + 24 = x, we can simplify it step by step:

1. Distribute the 0.8 to x and -5: 0.2x + 0.8x - 5 + 24 = x

2. Combine like terms: 1x - 5 + 24 = x

3. Simplify: x - 5 + 24 = x

4. Combine like terms: x + 19 = x

5. Subtract x from both sides: 19 = 0

The equation 19 = 0 is not true, which means there is no solution for this equation. This implies that there is an error in the given information or calculation.

Please double-check the information provided and ensure the calculations are accurate.