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# Simplifying Doughnut

This 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
do?

#### 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:

####
As a team:

### Getting started

### Tackling the problem

#### How to play

#### Rules

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Age 14 to 18

Challenge Level

This 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.

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
doughnut.

- Responding to the needs of others
- Helping others to do things for themselves.

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).

In silence:

Distribute the 16 domino cards randomly
amongst the team (four cards each).
Players pass dominoes to other team members in order to help one another complete their doughnut.

- No one can talk or give non-verbal signals to other members of the team.
- Each member of the team starts with four dominoes in front of them.
- The dominoes in front of each person should be visible to everyone.
- 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 the hint cards if after a period of five minutes the team is not making any progress.

Account of an investigation which starts from the area of an annulus and leads to the formula for the difference of two squares.

A task which depends on members of the group noticing the needs of others and responding.