Stage: 3 Challenge Level: 
Five numbers are added together in pairs to produce the following answers:
0, 2, 4, 4, 6, 8, 9, 11, 13, 15- What are the five numbers?
Games. Working systematically. Selecting and using information. Factors and multiples. smartphone. Visualising. Trial and improvement. Multiplication & division. Positive-negative numbers. Addition & subtraction.
Published January 1997.
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