This
activity is closely linked to The
Pied Piper activity in that it is a problem-solving situation
that requires some knowledge of numbers and their properties.
Possible approach
It would be good to withhold information that is obvious to
the teacher and just present the facts as on the
problem page.
Key questions
How are you doing this activity?
Possible extension
Give pupils the opportunity to invent other challenges of
their own having worked out the answers.