Well, let's think the problem through for a moment and see what we find. The problems tells us how much Kevin saves per week. So, if Kevin saves for 2 weeks, how much money would he make? What if he saves for 5 weeks? What if he saves for 10 weeks? What mathematical operation did you use to find these answers? That gives us a method to determine how much Kevin will save after any number of weeks, but the problem wants us to go the other way around and say how many weeks it would take him to save a specific amount. We can think of that as "doing the opposite" of what we did before. So, what mathematical operation does that suggest you ought to use?