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Converting Decimals, Percents, and Fractions, a la Shmoop.

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You could think of decimals, percents, and fractions as three different languages for

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numbers. Naturally, you sometimes need to translate

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from one language to another. And lucky you, we’re here to help.

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This is where conversion comes in. Conversion is the time-honored Western tradition

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of forcing others to believe exactly the same things that you do.

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Actually, we’re talking about converting one “language” of a number into another.

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For example, your “friend” got detention two out of five days this week.

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That scenario could be expressed as a fraction. Or it could be expressed as a frantic exclamation,

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as in: <<DS voice>> “My parents are going to kill me!”

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Or we could turn it into a percentage, by calculating how many detentions your friend

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is on pace for over the course of 100 days. Remember, percent really means “per hundred.”

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Five times twenty equals one hundred, so we also multiply two times twenty, which equals

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forty. Now we have forty over one hundred, or forty

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percent. That 40% detention rate could also be expressed

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as 40 point zero percent. When you start listing your detention percentage

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with a decimal point, it may be a wake up call to get some help.

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To convert forty percent into a decimal, we simply move the decimal point two places to

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the left. This gives us the decimal zero point four.

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Great batting average. So two-fifths equals forty percent equals

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zero point four. Let’s try a quick drill.

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What percent is zero point nine? Ninety percent. Good free throw percentage

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for basketball. Bad survival rate for appendectomies. Now let’s turn it into a fraction.

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Since percent means per hundred, we know ninety percent is really ninety out of one hundred.

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We can reduce it to make everything nice and neat.

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Ninety and one hundred can both be divided by ten, giving us nine-tenths.

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Are you fluent in decimals, percents, and fractions yet?

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Don’t worry if you’re only 50% of the way there.

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In that case, you only have 60% more to go. Wait…

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