



 
Hi Christine, This is a new term to me but I can guess. I think the teacher is trying to improve her students' mental arithmetic by helping them see products or factors that they already know. In your example of 8 × 25 I know that 4 × 25 = 100 (four quarters make a dollar) and 8 = 2 × 4. Thus
The object is to do this in your head rather than writing it down. I hope this helps,  


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