Elizabeth has 10 reusable water bottles. She loses 2 water bottles at school. Then someone steals 1 of her water bottles at dance practice. To avoid any future theft of her water bottles, Elizabeth places 3 stickers on each of her remaining bottles. How many stickers does Elizabeth use in total on her water bottles? Let's be accurate as possible.
Elizabeth has 10 - 2 - 1 = 7 water bottles. Elizabeth uses 7 * 3 = 21 stickers.
The answer: 21.