Stage: 2 Challenge Level: 
Thank you to Alistair who goes to Histon Infants School for the answer to this problem. He joined the dots to find the number $9$. Well done!
Practical Activity. Games. Working systematically. Factors and multiples. Trial and improvement. Addition & subtraction. Multiplication & division. Visualising. Compound transformations. Interactivities.
Published February 2002.
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