Let's assume that the total number of pages in this book is x. The number of pages that Naughty had already read was x +5 + 24, which was a total of x +5+24. The remaining pages make up two-thirds of the total number of pages, so there are: x÷5+24 + x/2 = x The above formula was simplified: x/2 + 24 = x After the reduction, it was obtained: x/2 = 24 Solution: x = 48 Therefore, the total number of pages in this book was 48.