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Why do we flip and multiply to divide fractions?

The Flip Trick
Why do we flip and multiply to divide fractions?
You've probably been told the rule a hundred times: to divide fractions, "~~flip the second one and multiply~~." It work

You've probably been told the rule a hundred times: to divide fractions, "flip the second one and multiply." It works. It always works. But why? Today we crack open this magic trick and find the perfectly ordinary machinery humming inside.

First, let's remember what dividing even means. When you ask "12 divided by 3," you're really asking: "How many groups of 3 fit inside 12?" The answer is 4. Division is just counting how many times one amount fits inside another.

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