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- [Instructor] We're told that Katie made a table
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to show how much time she spent on homework last week,
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and so we can see the different subjects
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and then how much she spent in terms of hours.
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So in math, she spent 3/4 of an hour,
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reading, 7/8 of an hour,
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writing, 3/6 of an hour,
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and then science, 5/10 of an hour.
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And then they ask us on which activities
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did Katie spend more than 2/3 of an hour?
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So pause this video and see if you can figure that out.
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All right, so we essentially have to figure out
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which of these fractions are greater than 2/3 of an hour?
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Which are greater than 2/3?
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And this is all in terms of hours.
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So first let's just think about representing 2/3,
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so let me do it like this,
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and I'm going to hand draw it
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so it's not going to be perfect.
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But if this is a whole right over here,
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I could split it into three equal sections,
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so I'm gonna try to do that.
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Let me see, does that look about right?
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So three equal sections,
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so that would be 1/3 that would be 1/3,
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and then that would be 1/3,
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and then 2/3 would be two of them,
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so I'll pick these first two.
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Well, it doesn't have to be those first two,
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so that's 1/3 and then 2/3.
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So let's see if we can draw a similar visual
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for each of these.
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So what about 3/4?
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So once again,
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let's make this a whole.
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And now if I want to think in terms of fourths,
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I have to divide it into four equal sections,
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so let's see.
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If I divide it, that will be two equal sections,
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and then I can divide each of those
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into two equal sections, so let's see.
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Maybe something like this,
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and then like this.
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So it's hand drawn, but these are four equal sections,
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and so this would be a fourth,
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that would be a fourth, and that would be a fourth,
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and that would be a fourth.
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4/4 make a whole,
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so three of those fourths would be one,
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two, and then three.
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And so you can see, and I've drawn it pretty close.
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It's not perfect 'cause it's hand drawn,
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but you can see that 3/4 is more of a whole than 2/3.
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It's greater than 2/3.
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So Katie spent more than 2/3 of an hour on math
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because 3/4 is greater than 2/3,
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so I like this one right over there.
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I'll just put a square or circle around the ones
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that she spent that extra time on
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or the more, the greater than 2/3 of an hour on.
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And I'll think about reading, 7/8.
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So to compare that, I will, once again,
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make a whole here,
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and then I want to think about 7/8,
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so I'm gonna split into eight equal sections.
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So let's see, that will split into two equal sections,
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and then, then I can go to four equal sections,
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and then if I split each of those into two,
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this would be eight equal sections,
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so it may look something like this.
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Not perfect, but I think it will get the job done.
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So each of these are 1/8,
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so 7/8 are going to be one, two, three,
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four, five, six, and 7/8.
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Clearly, once again,
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greater than our 2/3 that we have in purple.
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So she spent more than 2/3 of an hour on reading.
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Now what about writing?
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3/6, what would that look like?
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Well, I'll do another one right over here.
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So if that is a whole,
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well, actually let me split it to thirds first,
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since we already have a bit of a reference there.
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We can look up there and we can see.
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Those are thirds and if we split each of those into two,
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we're going to have sixths,
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'cause we'll have six equal sections.
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So it would look something like that,
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and then three of those six,
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well, that's one, two, and three.
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So we can see that 3/6 is less than 2/3
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so I'm not gonna circle that one.
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She didn't spend more than 2/3 of an hour on writing,
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and then last, but not least, science.
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5/10.
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Well once again,
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we could make a whole here,
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and let's see.
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I want to do into 10 equal sections,
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so that's two equal sections,
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and each of these, I can do into five equal sections.
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Let's see.
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One, two, three,
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four, five, I can do a little bit neater than that,
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three, four and five,
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and then one,
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two, three,
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four and five.
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I can make it a little bit neater,
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but I think this will get us
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to where we need to get to.
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So these are each 1/10.
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I could write 1/10, 1/10,
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I could do that for all 10 of these,
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but we care about five of these tenths,
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so one, two,
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three, four, five of those tenths.
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And notice, 5/10 is the exact same thing as 3/6,
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and like 3/6, it is less than 2/3.
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So which activities did Katie spend more than 2/3
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of an hour on?
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Clearly, math and reading.