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We're asked to shade 20% of the square below.

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Before doing that, let's just even think about

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what percent means.

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Let me just rewrite it.

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20% is equal to-- I'm just writing it out as a word-- 20

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percent, which literally means 20 per cent.

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And if you're familiar with the word century, you might

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already know that cent comes from the Latin

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for the word hundred.

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This literally means you can take cent, and that

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literally means 100.

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So this is the same thing as 20 per 100.

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If you want to shade 20%, that means, if you break up the

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square into 100 pieces, we want to shade 20 of them.

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20 per 100.

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So how many squares have they drawn here?

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So if we go horizontally right here, we have one, two, three,

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four, five, six, seven, eight, nine, ten squares.

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If we go vertically, we have one, two, three, four, five,

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six, seven, eight, nine, ten.

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So this is a 10 by 10 square.

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So it has 100 squares here.

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Another way to say it is that this larger square-- I guess

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that's the square that they're talking about.

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This larger square is a broken up into 100 smaller squares,

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so it's already broken up into the 100.

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So if we want to shade 20% of that, we need to shade 20 of

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every 100 squares that it is broken into.

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So with this, we'll just literally shade in 20 squares.

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So let me just do one.

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So if I just do one square, just like that, I have just

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shaded 1 per 100 of the squares.

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100 out of 100 would be the whole.

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I've shaded one of them.

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That one square by itself would be 1%

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of the entire square.

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If I were to shade another one, if I were to shade that

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and that, then those two combined, that's 2% of the

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entire square.

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It's literally 2 per 100, where 100 would

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be the entire square.

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If we wanted to do 20, we do one, two, three, four-- if we

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shade this entire row, that will be 10%, right?

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One, two, three, four, five, six, seven, eight, nine, ten.

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And we want to do 20, so that'll be one more row.

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So I can shade in this whole other row right here.

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And then I would have shaded in 20 of the 100 squares.

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Or another way of thinking about it, if you take this

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larger square, divide it into 100 equal pieces, I've shaded

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in 20 per 100, or 20%, of the entire larger square.

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Hopefully, that makes sense.

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