Before you try this activity, you might like to have a go at Number Balance and Getting the Balance, if you haven't already.

Here is a balance, or equaliser, which you might like to investigate:

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Now, what about a balance that has halves on it?

Imagine we hung a weight on the number 7 on the left-hand side. Let's say we can only use the "halves" on the right. Which two numbers on the right-hand side could you hang weights from so that it would balance?

For example, you might have a weight on the $\frac{1}{2}$ and the $6\frac{1}{2}$.

Where else could you hang two weights on the right-hand side to make it balanced?

You can set yourselves all kinds of problems with this new set-up.