Hi, I have to admit I am new to this forum, but it looks very good! I'm a 14 year old maths freak, so I often look up previous past maths competitions, papers etc, and analyze them. However I am stuck on this particular question. I was wondering if someone could give me guidelines on ways to solve it, and what sort of catergory this sort of problem falls under? It is quite unique.
Yenko the Bulgarian goatherd drives his father's goats into a valley each morning and lets them browse there all day before driving them home in the evening.
He notices that each morning the goats immediately separate into groups and begin to feed. The number and sizes of the initial groups vary. Some days there are nine or more groups; on other days, there are three or fewer. There can be groups of one or the whole herd can form a single group.
About every five minutes one goat breaks away from each feeding group and these breakaway goats form into a new group.
Yenko has noticed that by the afternoon, even though the goats continue their regrouping, the sizes of the groups have stabilized, and there are always seven feeding groups.
a.) How many goats are there in the herd?
What are the sizes of the feeding groups once they have stabilized?
Yenko's father then sells two of the goats. Over the next week, Yenko notices that things have changed. The sizes of the feeding groups no longer stabilize. There are not always seven groups. Nevertheless, a cyclic pattern of sizes develops every day.
b.) Find at least two possible cyclic patterns of sizes.