Stage: 2 and 3 Challenge Level: 
Having chosen your $4$ consecutive numbers you place $+$ and $-$ signs in between them.
You have $3$ empty spaces, so how many possible combinations are there for arranging the $+$ and $-$ signs?
Are you sure you have found them all? How will you know?
Games. Addition & subtraction. Visualising. Investigations. Creating expressions/formulae. Generalising. smartphone. Working systematically. Positive-negative numbers. Area.
Published November 1997,January 2007.
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