This problem is aimed at
interested and enthusiastic students: although we don't
recommend it for mainstream classroom use it provides enrichment
and will develop mathematical thinking and knowledge.
Like all NRICH problems it
has been carefully designed to be full of mathematical interest and
as such might be used in a variety of ways: you might suggest that
keen students consider the problem in their own time, use it for a
maths club at school or use it in class as a vehicle to foster
discussion and mathematical thinking. See our Teachers Guide to Getting Started
with rich tasks for more
suggestions and ideas.
This problem will be of particular interest to students considering
a university course containing an element of mathematical