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'Simplifying Doughnut' printed from http://nrich.maths.org/
is one of a series of problems designed to develop learners' team
working skills. Other tasks in the series can be found by going
to this article.
What are you aiming to
For the task:
The aim is for every member of the team to end up with a set of
four dominoes which join together to form a "doughnut" where
touching ends are algebraically equivalent. Like this:
The task is only successfully completed
when everyone on the team has completed their domino
As a team:
- Responding to the needs of
- Helping others to do things for
You will need to work in
a team of four. If you have a fifth person available - use them as
an observer (see guidance below).
Distribute the 16 domino cards
amongst the team (four cards each).
Tackling the problem
How to play
Players pass dominoes to
other team members in order to help one another complete their
- No one can talk or give non-verbal signals to other members of
- Each member of the team starts with four dominoes in front of
- The dominoes in front of each person should be visible to
- Team members can only give dominoes; they cannot take dominoes
from someone else.
- Each team member must have at least two dominoes in front of
them at all times.
Use an observer to check
that the team obeys the rules and to keep a record of when members
of the team help someone else (rather than, for example, when they
just pass a piece on without looking at what the other person or
team actually needs).
Observers can offer one of
cards if after a period of five minutes the team is not making