Xiaowen had read two-fifths of the book, which meant that Xiaowen had read 170 pages divided by 2 = 85 pages. There were still 170 - 85 pages = 85 pages that he had not read.
If a book has been read three-fifths of the way and there are 15 pages left, then the number of pages read is the number of pages not read: Number of pages seen/number of pages not seen = 3/5/4/5 = 3/4 Therefore, the number of pages that had been read was four-thirds of the number of pages that had not been read.
Suppose the book has x pages. It was known that two-fifths of the book had been read, and the remaining pages were 135. Therefore, he read this book in total: 135/(2/5 + 1) = 625/7/5 = 1275 pages. Since the total number of pages in the book is x, there are: x = 1275 pages. Therefore, the total number of pages in the book was: x = 1275 pages.
He had clearly read four-fifths of the storybook, and there were still 16 pages left to write the equation: He had clearly read 4/5 of the storybooks, and there were 16 pages left. 1 + 4/5 = 9/5 books Because I have read 4/5 storybooks, each storybook has: 4/5/1 = 8/15 pages Therefore, this book had: 9/5 × 8/15 = 96/15 pages It was about six pages.
If Xiao Hong had already read 40 pages of a book, which was two-fifths of the book, then Xiao Hong had already read 20% or 0.2 times the book. How many pages are there in the book? You can divide the number of pages by the number of pages in the book: (100% - 02) / 100% = 90% Therefore, Little Red only had 10 pages left.
The total number of pages that Xiao Ming had read was 150. He had already read three-fifths of the total number of pages, which was 3/5 = 6%. Therefore, Xiao Ming had already read about 6% of the pages, and the remaining pages were 150 - 6%= 144 pages.
This book was left: Two-fifths of the book is 18 pages, 2/5 = 9 pages (with two decimals) Therefore, there were still nine pages left in the book.
Let's say the book has $x$pages. Reading 15 pages a day, it would take Xiaohong $x$days to finish reading this book. The remaining pages were three-fifths of the book, which was $025x$. According to the question, it would take Xiaohong four days to finish reading this book. Therefore, we can write the equation: $$ x + 025x = 025 \times (x+4) $$ Solve this equation: $$ x = 30 $$ So this book has 30 pages.