Subject: Why does using reciprocals to divide fractions work?
Date: Sun 1/31/99 8:24 AM
From: Sally Ember

I have two questions about basic mathematical rules:

  1. why does using reciprocals to divide fractions work? What are we really doing when we do that?, and
  2. why does moving the decimal point over the number of places in the multiplicands in order to correctly place the product's decimal point work? What are actually doing there?

I teach basic math to adults in a night school, and the concepts are more important to them than the rules. I asked a math teacher of 20 years these questions, and he couldn't answer them except to say: these are the rules....

'THAT'S NOT GOOD ENOUGH!!! HELP!!!!?????

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