Suzanne walks four miles every third day. What is the fewest number of miles she can walk in February?
28 days in February.
Every third day is 28/3 = 9.333 = 9 days of walking.
9*4 = 36
She has an ON OFF OFF pattern. We want to maximize OFF days. Let's start the pattern on day zero (Jan 31st). So now she is going OFF OFF ON.
Since that's a 3 day rotation, we can say that every FULL 3 day segment is one walk. 28/3 = 9.333. Drop the decimal since we just proved it's an off day, you get 9.