Stage: 2 Short Challenge Level: 
On the planet Zargon ........
These are ziffles: $56, 105, 28, 63, 49$
These are not ziffles: $100, 18, 65, 9, 76$
Only two of these are ziffles: $16, 14, 57, 24, 70$
What is a ziffle?
Generalising. Properties of numbers. Interactivities. 100 square. Odd and even numbers. Addition & subtraction. Factors and multiples. Divisibility. Working systematically. Multiplication & division.
Published June 1999.
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