I am new to the forum, and I am sure it will be evident by this first question, but I hope to learn a lot here.(adsbygoogle = window.adsbygoogle || []).push({});

so.. here is what I was thinking about that prompted me to look for a math forum. Say I have (20cm)^{2}. That would be 400 square centimeters, or, 4 square meters? Now, what if I convert to meters before squaring? Then, I have (0.2 m)^{2}, or .04 square meters... 4 square centimeters? Why does this not work? When should I be converting to units? Before or after multiplication.

Thanks for any input.

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# When should I be converting to units?

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