Worked example: Recognizing fractions
About this video
Sal counts equal parts to name the fraction of a shape that is shaded red. A circle with 7 of 8 parts shaded is 7/8, a bar with 8 of 9 parts shaded is 8/9, and a circle with 7 of 9 parts shaded is 7/9. He shows that 'seven over eight' can be written stacked or with a slash, 7/8.
You'll be able to
- count the equal parts in a shape and the parts that are shaded.
- write a fraction for the shaded part of a shape.
- write a fraction stacked or with a slash, like 7/8.
Key words
- fraction
- A number that shows part of a whole, like 7/8.
- equal parts
- Pieces that are all the same size.
- shaded
- Coloured in, so we can see which parts we're counting.
Transcript
- [Voiceover] What fraction of the circle is shaded red? So let's see, this circle is divided into one, two, three, four, five, six, seven, eight equal parts, and of those eight equal parts seven are shaded red. So, we can say that seven out of eight are shaded red, and this isn't how we traditionally seen fraction when we've written them.
When we've written them we've written it like this. We have written seven over eight are shaded red. And actually, let me do it in that color, oh, I don't have that exact, let me get closer to an actual red color. So, we could literally say seven out of, and then we need like a grey color was, was the non-shaded.
Seven out of a total eight are shaded red. Are shaded red, that's how we're used to seeing it, but sometimes, or usually when we type it in there's no way to write the seven over the eight, so instead, instead we write seven over eight. Over eight are shaded red, or seven out of eight.
So, let's do that. Go back to what we we're doing. So, seven out of eight are shaded red. Let's check our answer. Let's do two more of these. What fraction of the bar is shaded red? So, the bar has one, two, three, four, five, six, seven, eight, nine equal sections, and eight of them are shaded red.
So, we can say that eight out of nine are shaded red, or eight-ninths, or eight over nine. Let's do one more. What fraction of this circle is shaded red? So, we have one, two, three, four, five, six, seven, eight, nine equal sections. Did I count that right? Let me count again.
One, two, three, four, five, six, seven, eight, nine equal sections, and of those one, two, three, four, five, six, seven are shaded red. So, seven out of nine, or seven-ninths are shaded red.
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