Denise's fraction quiz

I want to point out to you a post by Denise at Let's Play Math. She has a quiz concerning fraction rules: can you explain to your children why this way or why that way, as concerning fractions?

Quiz: Those frustrating fractions

QUOTE:
Question #1

If you need a common denominator to add or subtract fractions, why don’t you need a common denominator when you multiply?

Maybe you can explain why, maybe you can't. But don't worry. She's going to continue the topic and explain all of these, on her blog. Don't miss that.

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