Tim can use the equation 50 ÷ 10 = 5 to find the number of pages he used in his book.
The equation Tim can use to find the number of pages he used in his sticker book is 50 ÷ 10 = 5. This equation divides the total number of stickers (50) by the number of stickers put on each page (10), resulting in the number of pages used (5). So, the correct equation is 50 ÷ 10 = 5.