This book had a total of 180 + 5/6 = 195 pages.
This book has a total of $90+40%<<20>>= 1620$pages. Of which, 40% of the pages were already read by Xiao Ming, and the remaining 90 +80=170 pages were unread.
This book has a total of $90+ 40%$ $×$pages. Substituting 40% into the above formula: $90+04×$ $×$pages = $90+04×$ $×$ (100-90) = $90+04×$ $× $10 = $90+04×$ $× $100 = $90+40=130$pages Therefore, the book had a total of 130 pages.
There were 170 pages in a book. He had already read 90 pages, so there were still 80 pages left.
Lil 'Fatty had already read half of the book. Three pages were missing, which meant 1/2 - 1/2 + 3 = 2/3 pages. Therefore, Lil 'Fatty had already read 2/3 of the pages and there were still 90 pages left. This meant that the book had a total of 90/2/3 = 90/3 = 300 pages. Therefore, the book had a total of 300 pages.
This book had: 39 + 2/5 = 39 + 06 = 406 pages. Because the number of pages in a book must be an entire number, the decimals needed to be rounded to the nearest whole number. Therefore, the book had a total of 40 pages.
He had already read 3/4 of the book, which was 1/2 of the pages, so the remaining pages should be twice the number of pages in the book, which was 24 pages. The total number of pages in the book = 1/2 × 120 pages. Therefore, the book had a total of 120 pages.
Xiao Ming read 39 pages and there were 52 pages that he did not read. The percentage of pages that Xiao Ming read in the total number of pages in this book is: 39 pages/52 pages = 7385% Therefore, the number of pages that Xiao Ming read accounted for 7385% of the total number of pages in the book.
This comic book had a total of 19 pages. He had already read 7 pages, so there were 19 - 7 = 12 pages left.
Assuming that this storybook had $x$pages, then the number of pages Little Light read every day was $15/div4 = 375$pages. Little Light had already read $4$for days, so the remaining pages were $x - 4/375 = x - 1125$. Because the number of pages Little Light reads every day is fixed, the number of pages can be expressed as: $$x - 4 \times 375 = 375 \times 4 - 1125$$ The above formula was simplified to: $$x = 48$$ Therefore, there were still $48 - 1125 = 3675 pages of this storybook that he had not read.
Xiao Ming read a total of $4/15 = 60$pages in 4 days. The remaining pages are $2/5$of the book, so the book has a total of $2/5/60 = 48$. Thus, the book had a total of 48 pages.