There are 20 stickers on a page. If you have 12 pages of stickers but lose one of the pages, then how many stickers would you have?
After losing one of the pages you have 12 - 1 = <<12-1=11>>11 pages of stickers.
If each page has 20 stickers on it, you have 11 x 20 = <<11*20=220>>220 stickers.
#### 220