Tear off a page, the page number is missing two connected numbers, the odd number is in front and the even number is in the back; The sum of the remaining pages is odd. If you tear off that page, the total of that page must be odd, so the total of the original page must be even.

Then, assuming that the number of pages in the book is n and n is even, the total number of pages should be (1+N)*N/2, that is, N*N is about 14338, and the square of 120 is 14400, then n is most likely/kloc. This is a similar problem. The question is,' One page of a book is torn off, and the sum of the remaining pages is 7 169, which page is torn off'. Just follow the previous formula. choose one