Question

⬆️Question is up there​

Answer 1

Let $n$ be the total number of stickers. If she puts 21 stickers on a page, she will fill up $p$ pages such that

$n = 21p + 14$

Suzanna has between 90 and 100 stickers, so

$90 \le n \le 100 \implies 76 \le n - 14 \le 86$

$n-14$ is a multiple of 21, and 4•21 = 84 is the only multiple of 21 in this range. So she uses up $p=4$ pages and

$n-14 = 4\cdot21 \implies n = 4\cdot21 + 14 = \boxed{98}$

stickers.