On a supermarket shelf, there are 45 packs of cereals. Among these, there are five packs whose sell-by date is less than a week from now. Lena selects four packs of cereals at random and intends to consume them after a week, since she has another pack of cereals at home. What is the probability that at least one of the four packs she bought will have past its sell-by date a week from now?