WEBVTT
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Let's take a very detailed look on slicing and counting the slices of our standard pizza.
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First off, let's say you've just been sliced in the box and here it is. We have 8 slices in 8 pieces.
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It's 8 over 8 so we have 1 whole pizza.
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So, the friend comes along and asks for a slice and takes this away.
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Now we have 7 out of 8.
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Then someone else comes up and then I come in here and I'm going to walk down a couple of slices.
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So, we're going to have 6 and 5 and 4 and 3 slices are going to be left over.
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Then you have 2 slices left over and then someone better hurry and get the left over slices.
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So, I want to grab that one and then of course everyone battles for that very last slice.
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So, where it eats the fastest, gets that last slice.
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So, when you have 1 slice left, you grab that, what do we have left over? Well, we have now 0 slices out of the original 8.
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That's when we have over here. So, 0 over 8 or 0 8 is just 0. We have no pizza left.
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This brings about some more definitions. Let's take a look at some other stuff.
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If a is any number except 0, a divided by a equals 1 and 0 divided by a equals 0.
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A over 8 means any number except 0 divided by itself is 1.
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0 over 8 means 0 parts of any number except 0 of original cuts is just 0.
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So, the a over a rule can be seen right here. We have 8 divided by 8 and there's 1. We have 8 slices out of 8, that one whole pizza.
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And then we ate the whole pizza so nothing's left. So, 0 slices out of the original 8 is 0 is an example of the 0 over a or any number rule.
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Now, the a over a rule is also very important because later on we're going to need to be able to rewrite the number 1, change its form for our convenience.
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So, there may be an instance where instead of 1, I'd like to have something that looks like 8 over 8, for instance, or how about 2 over 2 or 3 divided by 3.
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So, having this rule is going to be very important and very handy very soon.
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We have like fractions when 2 or more fractions have the same denominator.
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This matching denominator is the common denominator.
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Are these like fractions? Well, look at the denominators. They're all the same.
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So, since they have the same denominator, they're like fractions and again you can say this is a common denominator of 8.
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I want you to look very carefully at this one. So, here now we have 4 different slices.
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But, how much really of the entire pizza do we have left? So, we have 4 out of 8. But, really this is just 1 half a pizza.
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So, 4 eighths is really the same as 1 half. Let me think about it.
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What if again, again someone combined and put those slices right there. So, now you have 2 out of the 8 slices.
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But, look at this. Compare it with this thing. See, this is a quarter of the pizza left over.
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So, that is 1 fourth. Really. So, let's now try to generalize and talk more about this.
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Equivalent fractions are fractions that are different in form but have the same value.
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We will use an equal sign to mean equivalent fractions.
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So, now we can say that 4 eighths is equivalent to 1 half and we can say 2 eighths is equivalent to 1 fourth.
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What common fraction or fractions can you hear that's being represented by these stars?
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Well, out of a group of 6, 1, 2, 3 of them are different color. So, that's an answer.
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I can say 3 out of the 6 stars is a common fraction. But, look at this again with it.
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Half the stars are blue, half the stars are gray. So, I can just say 1 half is also common fraction.
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But, we just talked about the same group of stars. Therefore, we can say 3 6 is equivalent to 1 half.
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So, you think about it.
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Now, we saw earlier that 4 eighths is equivalent to 1 half.
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And we just saw in our previous example that 3 6 is also equivalent to 1 half.
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They're all equivalent to 1 half. In fact, there's an infinite number of equivalent numbers to 1 half.
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You could have something like 1,234 divided by 2,468. And that is really 1 half.
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Now, if you put this on a test, I mean it's correct but it would really annoy your teacher.
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So, one of the things we want to do is try to make the numbers as small as possible.
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As low in value as we can. But, still mean the same thing. This really does mean the same as 1 half.
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But, this is easier on the eyes than that.
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So, all this that we're talking about brings us to our next definition.
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A reduced fraction is a fraction that is in its simplest form.
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4 eighths and 3 6 are not reduced fraction because there exists something else that is in a lower form.
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Well, how can we be sure something is in a reduced form? How can we change maybe something like this or like this?
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So, let's do that next.
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Now, I want to find a method that would automatically and systematically reduce 4 eighths into its reduced form.
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Well, looking at the 4 and I wanted to get a 1, what can I do to 4 to get 1?
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Oh, I can divide by 4. 4 to divide by 4 is 1.
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Ah, okay, so let's try that. I'm going to divide this by 4.
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Yep, the answer is 1.
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But, anything you do on the top of a fraction, you better go on the same thing on the bottom of the fraction.
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So, I need to divide this by 4. Would that give us what we want to?
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Yeah, 8 to divide by 4 is 2.
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Hmm, would that work with the 3 6? Let's try that.
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So, if I have 3 6 and I want this to be 1 half, what can I divide 3 by?
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Well, 3 divided by 3 is 1. 6 divided by 3 is 2.
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So, that seems to work.
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The procedure we just did doesn't work for addition or subtraction.
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You can only divide or multiply numbers in the number of end denominators by the same numbers to get a reduced fraction.
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Let's see that with our previous example.
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Of course, you might ask, well, why just divide? Maybe we can do something else.
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Other ways are getting a 1 from a 4, like subtracting 3.
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So, if I have 4 and I go minus 3, let's extend that, the answer is 1.
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And 8 minus 3 is 2, right?
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No, we don't get our half right there.
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Oh, so this rule is not going to work. See, we get ourselves a 5.
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So, subtracting, or even adding that matter, doesn't work.
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A fraction is in lowest terms or simplest form, if there are no factors in common, other than 1, between the denominator and the numerator.
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Now, a mixed number isn't in lowest terms unless the fractional part is in lowest terms.
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So, this mixed number, 3 and 2, 4, is not in lowest form.
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But, let's see, 3 and 1 half.
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The cancellation method. Start canceling common factors,
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mentally dividing the numerator and denominator by the same number.
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Repeat this until you cannot do so anymore.
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I want to simplify this fraction right here.
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So, first off, about those two, everything is even.
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So, that can actually divide through by 2.
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So, I'm going to extend this and go divided by 2, divided by 2.
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And what do I get as an answer? Well, I'm going to get 12, 15.
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Now, have I simple facts completely?
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Well, no, I can still divide things that are common to both.
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And I know that there is a 3 in 12 and there is a 3 in 15.
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So, I can divide the top by 3 and the bottom by 3.
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And I'm going to get 4, 5.
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Now, can we reduce 4, 5th, any more and any smaller?
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Well, other than 1, nothing divides into both.
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So, successfully reduce this fraction into the lowest terms as possible.
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Now, we have to do quite a bit of writing here, divided by 2, divided by 2, divided by 3, divided by 3.
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Let's now do the same problem over again, but in a much slicker and faster way.
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So, here we have our 2430.
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Let's cancel common terms top bottom.
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So, like before we noticed there was a 2 in each.
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So, I'm going to cancel the 24 and make that 12.
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So, cancel a 30 and make that 15.
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And I can continue canceling.
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There is a 3 in each.
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So, 12 divided by 3 is 4.
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15 divided by 3 is 5.
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See, that's going to be my answer.
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So, I'm going to write down 4 fifths.
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And that is my final answer for this.
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And this is what's called the cancellation method.
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So, let's divide it by 2 and divide it by 3.
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Let's combine that.
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We can divide by 6.
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So, 24 divided by 6 is 4.
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30 divided by 6 is 5.
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And that's going to give us our answer.
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We're going to have 4 fifths.
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See that?
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So, trying to find the greatest factor that's in common is a very fast way of cancelling this fraction
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and having it reduce the lowest terms.
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Notice what I said?
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The greatest common fact?
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Well, that comes into play for our next definition.
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The GCF method.
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To simplify a fraction, find the greatest common factor, or GCF,
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of the denominator and the numerator, then divide the denominator and numerator by the GCF,
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or cancel the GCF out.
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By the way, the GCF is also known as the highest common factor or the greatest common divisor.
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Now, finding the GCF is something that I do in detail in lesson number 5.
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So, if you're not sure how to do that, you need to go to that lesson.
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Now, I want to find the GCF of the 2430.
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So, here's my 24, here's my 30th.
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I'm going to use the factor tree technique.
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So, I think a 2-multi-cloud gives me 24.
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Oh, how about 4 times 6?
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4 can be broken down into 2 times 2.
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6 can be broken down into 2 times 3.
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Now, what about 30?
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30, how about, oh, I see a 3 and a 10 right away,
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and then the 10 can be broken down into 2 times 5.
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So, now we want to look at, well, what did they have in common?
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Well, I see a 2 right here, and there's a 2 right there,
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and there's a 3 here, and there's a 3 there.
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So, a 2 times 3 is 6, and that is my GCF.
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And with that, I can go, okay, 24 divided by 6 is my 4.
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30 divided by 6 is my 5.
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That gave me my 4.5.
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Again, I've already done this, but I want to be a little more formal,
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and that I find a GCF, and it helps me reduce the fraction.
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And I think, well, why go through all this trouble?
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Well, one of the kind of big, it might be to your advantage.
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But you could always just cancel, like we did before.
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Find just anything that will work.
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And if you can do that, you'll eventually reduce it,
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but it may just take a little bit longer, but it could always be done.
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For example, 5, I would like to reduce this fraction to lowest terms.
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Now, okay, what method?
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Cancelation, GCF?
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Well, it's your call.
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Try both methods, if you like.
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I'm going to try to be a straightforward model.
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Okay, when I see something like this, first I'm noticing it ends with 5.
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That means I can divide everything by 5.
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And you can use a calculator by hand.
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So, 225, and I divide that by 5, I want to get 45 as an answer.
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315, divide that by 5, I'm going to get 63.
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And that's what I'm left with.
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So, 45, 63.
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Is that as far as we can go?
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Well, take more think about it.
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45, 63.
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What if you add the digits?
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4 plus 5, 9, 6 plus 3, isn't that?
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There's a rule that says, if you add the digits,
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and you're going to answer that the visible by 9,
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then that real number is the visible by 9.
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So, I can divide this by 9, and I want to get 5, and divide this by 9,
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and I want to get 7.
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So, I want to get a fraction of 5, 7.
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And we go even further with this.
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5, 7, I know.
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That's as far as I can go.
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So, we have reduced successfully our fraction.
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All graphing calculus can convert numbers in diffractions,
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and reduce them.
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On the text sensor calculators, all you need to do is look for the division key seen here.
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Now, when you press that key, it changes into a forward slash on the screen, like this.
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Now, to actually change the number into a fraction,
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you need to call the convert to fraction function.
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Where is that?
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Well, you press the math key, and then press enter, and you get something that looks like this.
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Now, let's go ahead and try this on an actual example.
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Reduce 225 to 115th to lowest terms.
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For our first step, we press the clear key right there.
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Now, we're going to input our fraction.
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225 divided by 315.
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Here's our fraction.
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Now, let's convert this to a reduced form.
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So, just press your math key, and then just enter, and enter again.
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Here it is.
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570s.
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Now, we've learned how to reduce a fraction to write in lowest terms.
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But what if I actually want the opposite?
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I want to actually change a half into something like this.
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Into 480s.
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480s is considered a higher form of a half.
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A fraction is in a higher form when the denominator and numerator are multiplied
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by the same non-zero number.
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And this example, we're asked to find a clear fraction to 3 quarters with this denominator.
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How do we do that?
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Very easy.
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First step, divide 36 by 4.
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So, 36 by 4 is 9.
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And then you go 9 times 3 to get 27.
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That's it.
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That's all you got to do.
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Let's try another example.
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So, for this fraction, I want to convert 511s into an equivalent fraction with this denominator.
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How do we do that?
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Well, we went through the steps earlier.
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I'm going to divide 110 by 11.
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If you do that, you get 10.
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Then you go 10 times 5 is 50.
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And sorry, you have to do this almost like a circle here.
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I go this, divide by that, get an answer, times it by this, and then that will give me this answer.
226
00:18:33.000 --> 00:18:41.000
So, it's very straightforward.
227
00:18:41.000 --> 00:18:47.000
For exercise 8, we're asked what fractions are represented by this?
228
00:18:47.000 --> 00:18:53.000
Well, you first have to figure out how many toll slices are there.
229
00:18:53.000 --> 00:18:54.000
So, let's count them.
230
00:18:54.000 --> 00:18:59.000
One, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, sixteen.
231
00:18:59.000 --> 00:19:02.000
So, there's a total of 16 slices.
232
00:19:02.000 --> 00:19:04.000
So, that's going to be my denominator.
233
00:19:04.000 --> 00:19:07.000
So, I'm going to write down 16.
234
00:19:07.000 --> 00:19:10.000
Now, how many of them are shaded?
235
00:19:10.000 --> 00:19:12.000
I have one, two, three, four.
236
00:19:12.000 --> 00:19:14.000
So, four.
237
00:19:14.000 --> 00:19:17.000
That's an answer.
238
00:19:17.000 --> 00:19:18.000
Is that the only fraction?
239
00:19:18.000 --> 00:19:20.000
No, we can reduce this.
240
00:19:20.000 --> 00:19:23.000
So, this is the same thing as divide by two.
241
00:19:23.000 --> 00:19:27.000
I can get two eighths and eight.
242
00:19:27.000 --> 00:19:29.000
What's up there?
243
00:19:29.000 --> 00:19:30.000
Divide by two again.
244
00:19:30.000 --> 00:19:34.000
I get one fourth.
245
00:19:34.000 --> 00:19:42.000
So, there's my answer.
246
00:19:42.000 --> 00:19:47.000
For exercise number nine, I'm going to place this minute hand someplace on the face of this clock.
247
00:19:47.000 --> 00:19:51.000
I want you to draw it on your paper.
248
00:19:51.000 --> 00:19:57.000
And then, I'm going to be asking you questions to convert fractions into its lowest form.
249
00:19:57.000 --> 00:20:00.000
So, let's go ahead and try this.
250
00:20:00.000 --> 00:20:08.000
So, let's say I'm going to start right here and 60 entire minutes have occurred.
251
00:20:08.000 --> 00:20:10.000
So, I want you to write down a fraction for that.
252
00:20:10.000 --> 00:20:14.000
For 60 minutes from 60 minutes.
253
00:20:14.000 --> 00:20:15.000
Well, that's easy.
254
00:20:15.000 --> 00:20:23.000
You just write down 60 over 60 and then the reduced fraction.
255
00:20:23.000 --> 00:20:25.000
Well, whenever you have the same number over itself, it was a rule.
256
00:20:25.000 --> 00:20:26.000
You memorize for that.
257
00:20:26.000 --> 00:20:28.000
The answer is just one.
258
00:20:28.000 --> 00:20:35.000
Which, of course, may exist because if 60 minutes have occurred, one hour passed.
259
00:20:35.000 --> 00:20:42.000
Now, let's move our minute hand to right here.
260
00:20:42.000 --> 00:20:43.000
50.
261
00:20:43.000 --> 00:20:49.000
Give me the fraction and it's reduced form.
262
00:20:49.000 --> 00:20:53.000
Well, write down 50 over 60.
263
00:20:53.000 --> 00:20:56.000
Very fast way to reduce it is just cut out the zeros.
264
00:20:56.000 --> 00:21:02.000
So, I'm left with 5, 6 as the final answer.
265
00:21:02.000 --> 00:21:07.000
Now, let's change the minute hand from here to right there.
266
00:21:07.000 --> 00:21:14.000
I want you to create the original fraction and then the lowest form.
267
00:21:14.000 --> 00:21:16.000
Well, 45 minutes have passed.
268
00:21:16.000 --> 00:21:21.000
So, now we have 45 over 60 equals.
269
00:21:21.000 --> 00:21:27.000
Now, we can start dividing these numbers by 5s or maybe 3s.
270
00:21:27.000 --> 00:21:30.000
But there's actually another way of thinking about this.
271
00:21:30.000 --> 00:21:33.000
How much of an hour has passed?
272
00:21:33.000 --> 00:21:35.000
Three quarters have been alright?
273
00:21:35.000 --> 00:21:40.000
So, that's a pretty slick way to find any answer.
274
00:21:40.000 --> 00:21:42.000
And try to think of that.
275
00:21:42.000 --> 00:21:45.000
Sometimes maybe we want the hour version versus the minute.
276
00:21:45.000 --> 00:21:49.000
But I still want you to write down the minutes with 60 first and then reduce.
277
00:21:49.000 --> 00:21:51.000
There's our answer.
278
00:21:51.000 --> 00:21:53.000
Now, let's try another one.
279
00:21:53.000 --> 00:21:57.000
Let's move our minute hand right there.
280
00:21:57.000 --> 00:22:03.000
Give me the original fraction and it's the lowest form.
281
00:22:03.000 --> 00:22:09.000
Well, we have 30 minutes have passed out of 60.
282
00:22:09.000 --> 00:22:12.000
But again, you want to be slick about this.
283
00:22:12.000 --> 00:22:15.000
It doesn't happen hours past.
284
00:22:15.000 --> 00:22:18.000
Happen now.
285
00:22:18.000 --> 00:22:28.000
Alright, so now let's move our minute hand right there.
286
00:22:28.000 --> 00:22:34.000
Well, it looks like we have 25 minutes out of 60.
287
00:22:34.000 --> 00:22:36.000
And I want to reduce that.
288
00:22:36.000 --> 00:22:38.000
I don't have a slick way of doing that.
289
00:22:38.000 --> 00:22:41.000
So, let's just do some old-fashioned mathematics.
290
00:22:41.000 --> 00:22:49.000
And each 25 divided by 5 is 5, 60 divided by 5 is 12.
291
00:22:49.000 --> 00:22:53.000
So, that's going to be our answer.
292
00:22:53.000 --> 00:23:02.000
Now, let's go to right there.
293
00:23:02.000 --> 00:23:04.000
Well, it looks like 20 minutes have passed.
294
00:23:04.000 --> 00:23:09.000
So, I'll write that down 20 out of 60.
295
00:23:09.000 --> 00:23:12.000
And a lot of ways you can see this, you can say,
296
00:23:12.000 --> 00:23:15.000
well, this is just a third of an hour has passed.
297
00:23:15.000 --> 00:23:18.000
Or you can just do this by some canceling.
298
00:23:18.000 --> 00:23:19.000
There's a 10 in each.
299
00:23:19.000 --> 00:23:21.000
This is just two six.
300
00:23:21.000 --> 00:23:24.000
Cut these in half and you get one third.
301
00:23:24.000 --> 00:23:27.000
So, here's my one third.
302
00:23:27.000 --> 00:23:30.000
Well, big guess where we need to go next, right?
303
00:23:30.000 --> 00:23:33.000
I'm going to go right there.
304
00:23:33.000 --> 00:23:36.000
Here to try.
305
00:23:36.000 --> 00:23:39.000
Well, 15 minutes have passed.
306
00:23:39.000 --> 00:23:41.000
So, it's going to be 15 out of 60.
307
00:23:41.000 --> 00:23:46.000
And no big surprise, this is a quarter past the hour, right?
308
00:23:46.000 --> 00:23:51.000
So, it's just a quarter.
309
00:23:51.000 --> 00:24:00.000
Now, let's go right there.
310
00:24:00.000 --> 00:24:02.000
Well, 10 minutes have passed.
311
00:24:02.000 --> 00:24:04.000
Out of 60 total minutes.
312
00:24:04.000 --> 00:24:12.000
I can cancel my tens, a left of 1, 6th of an hour.
313
00:24:12.000 --> 00:24:20.000
Okay, let's move this to right there.
314
00:24:20.000 --> 00:24:23.000
Now, just a mere five minutes have passed in time.
315
00:24:23.000 --> 00:24:26.000
Out of a total of 16 minutes.
316
00:24:26.000 --> 00:24:28.000
5 to 5 by 5 is 1.
317
00:24:28.000 --> 00:24:32.000
60 to 5 by 5, we found it earlier was 12.
318
00:24:32.000 --> 00:24:34.000
And I'm going to make sense.
319
00:24:34.000 --> 00:24:36.000
There's one, two, three, two, three of 12 numbers here.
320
00:24:36.000 --> 00:24:40.000
I'm on the first one, so it's one 12th of an hour.
321
00:24:40.000 --> 00:24:42.000
Yep, I'm going to move this one more time.
322
00:24:42.000 --> 00:24:47.000
I'm going to move this to just a couple of tick marks right there.
323
00:24:47.000 --> 00:24:51.000
Just two of these.
324
00:24:51.000 --> 00:24:55.000
Give me the fraction and it's lowest form.
325
00:24:55.000 --> 00:24:59.000
Well, if two minutes have passed,
326
00:24:59.000 --> 00:25:02.000
out of 60 cannot be reduced.
327
00:25:02.000 --> 00:25:05.000
Well, they're both even, so I can just divide by 2.
328
00:25:05.000 --> 00:25:07.000
Two divide by 2 is 1.
329
00:25:07.000 --> 00:25:10.000
60 divide by 2 is 30.
330
00:25:10.000 --> 00:25:13.000
So, 1 30th of an hour has passed.
331
00:25:19.000 --> 00:25:26.000
Exercise 10 is actually designed for students who have access to these type of slices of pizza
332
00:25:26.000 --> 00:25:29.000
or perhaps these fraction circles.
333
00:25:29.000 --> 00:25:34.000
Now, the circles you may have can be different colors.
334
00:25:34.000 --> 00:25:36.000
And not necessarily we'll be matching this exactly.
335
00:25:36.000 --> 00:25:38.000
There's different companies make these types of products.
336
00:25:38.000 --> 00:25:45.000
So, with that in mind, I want you to take a look at this graphic right here.
337
00:25:45.000 --> 00:25:51.000
Alright, so I want you to try to use these types of fractions
338
00:25:51.000 --> 00:25:57.000
to create equivalent fractions to that graphic you just saw.
339
00:25:57.000 --> 00:26:00.000
And try to come up with as many as you can.
340
00:26:03.000 --> 00:26:07.000
Now, for the answer, there's many different ways in doing that.
341
00:26:07.000 --> 00:26:13.000
I'm going to use the pizza and I'm going to go from the smallest denominator to the largest.
342
00:26:13.000 --> 00:26:20.000
So, here I can actually use three quarters to represent the same shaded region as you saw in the graphic.
343
00:26:20.000 --> 00:26:24.000
Using 8th, here's what it looks like this.
344
00:26:24.000 --> 00:26:30.000
You have 1, 2, 3, 4, 5, 6 slices out of the 8th or an x fraction.
345
00:26:30.000 --> 00:26:35.000
Now, if you're using your 12th slices, this is what you can do.
346
00:26:35.000 --> 00:26:37.000
You can make 9 out of the 12 slices,
347
00:26:37.000 --> 00:26:41.000
we'll create the same shaded region as the graphic.
348
00:26:41.000 --> 00:26:44.000
As far as far as you can go with most of these fraction circles,
349
00:26:44.000 --> 00:26:48.000
but with the pizza, there's one more shape we can do.
350
00:26:48.000 --> 00:26:52.000
For our last way of combining these pizza slices,
351
00:26:52.000 --> 00:26:57.000
if now we have the slices of our 16th, these little ones right here,
352
00:26:57.000 --> 00:27:04.000
you can have 12 out of the 16th would create the same shape as the graphic I saw earlier.
353
00:27:04.000 --> 00:27:09.000
Now, a quick note, if you are in a classroom or at home trying to do this with these pizza slices,
354
00:27:09.000 --> 00:27:17.000
you wouldn't need two of these boxes, two of these sets to have enough of these 16th to do something like this.
355
00:27:17.000 --> 00:27:24.000
So, to conclude, all the fractions we created are called equivalent fractions.
356
00:27:30.000 --> 00:27:37.000
For exercise 11, I want you to take some time to simplify all the fractions listed.
357
00:27:41.000 --> 00:27:44.000
Well, for the first one, I notice there's a 5 in each,
358
00:27:44.000 --> 00:27:50.000
so I can divide by 5, I'm going to get 4, divide by 5, I'm going to get 9.
359
00:27:50.000 --> 00:27:56.000
So, to reduce this, I'm going to get 4 9s.
360
00:27:56.000 --> 00:28:01.000
Now, for the next one, 17 is a prime number.
361
00:28:01.000 --> 00:28:06.000
So, if this is going to reduce, there would need to be a 17 in the 51.
362
00:28:06.000 --> 00:28:11.000
So, either by hand, or you can calculate, you're going to say 51, divide by 17,
363
00:28:11.000 --> 00:28:14.000
and it goes into it three times.
364
00:28:14.000 --> 00:28:19.000
So, I can actually divide both of these by 17, I would have one left over,
365
00:28:19.000 --> 00:28:21.000
and I would have three left over here.
366
00:28:21.000 --> 00:28:27.000
So, my answer is going to be, wait, that's not quite the answer, right?
367
00:28:27.000 --> 00:28:31.000
It's very important to remember that if it's a negative, a negative state,
368
00:28:31.000 --> 00:28:35.000
a lot of people lose that when they're trying to simplify these.
369
00:28:35.000 --> 00:28:39.000
Now, for the next one here, 11 is a prime number,
370
00:28:39.000 --> 00:28:42.000
and 11 does not go into 14, so guess what?
371
00:28:42.000 --> 00:28:44.000
It's already reduced.
372
00:28:44.000 --> 00:28:48.000
Alright, so this one's a little sneaky, but I had to go at it.
373
00:28:48.000 --> 00:28:53.000
Here, what's the rule for reducing a mixed number?
374
00:28:53.000 --> 00:29:00.000
Well, the integer stays, and what you do is you want to reduce the 5, 20s.
375
00:29:00.000 --> 00:29:04.000
Well, both of them have 5 in them, so I can divide about by 5 is 1,
376
00:29:04.000 --> 00:29:12.000
and the value is 1, 20 divided by 5 is 4, so this would give us 8 and 1, 4.
377
00:29:12.000 --> 00:29:17.000
Now, for this last one, again, there was a rule that's a number over itself,
378
00:29:17.000 --> 00:29:22.000
it's just 1, so that's really all you need to do with that.
379
00:29:22.000 --> 00:29:26.000
Now, what is the rule of 0 divided by any number?
380
00:29:26.000 --> 00:29:31.000
Well, that's not 0. The answer is 0, so that's all we need to do for this one.
381
00:29:31.000 --> 00:29:36.000
And here, 6 divided by 0, we're not allowed to divide by 0,
382
00:29:36.000 --> 00:29:41.000
so you answer like this, undefined.
383
00:29:41.000 --> 00:29:45.000
That's important to do that.
384
00:29:45.000 --> 00:29:49.000
Well, this last one here, we'll get straight away, I know it's n with 0,
385
00:29:49.000 --> 00:29:52.000
so I can just cross those out, I can cancel those.
386
00:29:52.000 --> 00:29:56.000
And they're both events, I think this is 26 over 46,
387
00:29:56.000 --> 00:30:01.000
I can divide by 2, that will give me 13, I can divide this by 2,
388
00:30:01.000 --> 00:30:06.000
that will give me 23, and I really can't do anything with 13 and 23,
389
00:30:06.000 --> 00:30:11.000
so that's going to give me my final answer, 13, 23.
390
00:30:11.000 --> 00:30:25.000
Exercise 12 wants us to change 3-5 into an equivalent fraction that is in 30th,
391
00:30:25.000 --> 00:30:31.000
so I might not use 30, I want you to give it a try first.
392
00:30:31.000 --> 00:30:34.000
Again, this is one of the easiest problems we can have with fraction.
393
00:30:34.000 --> 00:30:37.000
And again, remember that's the circuit of the thing we did, we said,
394
00:30:37.000 --> 00:30:48.000
okay, 30 divided by 5 is 6, and go times 3, the answer is 18.
395
00:30:48.000 --> 00:31:03.000
Music