Meaning of 109%

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About this video

The video shows what 109% means: 109 per 100, or 109/100, which is more than one whole. It shades all 100 squares of a 10 by 10 grid to show 100%, then shades 9 more squares to show the extra 9%.

You'll be able to

  • explain that percent means per hundred.
  • write a percent like 109% as a fraction over 100.
  • shade a 10 by 10 grid model to show a percent greater than 100%.

Key words

percent
A number out of 100; 'per cent' means 'per hundred'.
whole
The complete amount, which is 100 out of 100, or 100%.
ratio
A comparison of two numbers, like 109 per 100.
Transcript

Show 109% by shading. So just as a bit of review, 109% if we were to write it out, would literally be 109 percent, which is the same thing as 109 per-- and I could write cent again, but that's getting old. Cent means 100, so it literally means 109 per hundred.

If you had 100 per 100, you're dealing with the whole, but now we have more than a whole. We have 109 per 100. We can actually write this as a ratio, or as a fraction. This is the same thing as 109 per 100. It's the the same thing as 109/100. So let's shade that in.

So we have a whole here, so we could consider this square a whole. In the last video, we counted. This is a 10 by 10 square. It is cut up into 100 pieces. So if we want 109 of those 100 pieces, what are we talking about? That means we're going to shade in all of the 100 right over here.

Let me do that in a new color. So we'll shade in all of this. If you just shaded that in, that would be 100%. That would be 100/100, or 100 per 100, or 100%. I think you're getting the meaning of all of this. I don't just want you just memorize this stuff. This really just means 100 out of 100, or a whole.

And you can see that this is the whole square. That's 100 out of 100 right there. The question is saying show us 109% by shading. We already did 100 per 100, but we need to do another 9, so let's shade in another 9. So now we have one, two, three, four, five, six, seven, eight, nine.

So this piece right here, you could almost view that is-- well, that is! That is 9% of an entire square. This is 100% of an entire square. If you considered this whole thing plus this blue area right over here, you are talking about 109% of one whole square. Hopefully, that made sense.

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