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How To Add And Subtract Fractions
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Remember that the denominator stays the same and is
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How To Add And Subtract Fractions
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If you want to add some fractions, let's look at an example and see how we do that. Let's add the fractions two quarters and one quarter. A good way to think about his is to look at the diagrams of these fractions. Good diagram would be to draw 2 circles and split these circles into 4. If we color in two quarters here and one quarter here, it's very clear what we expect our answer to be. Let's draw another diagram here and split it into 4 and we can see that is we take these 2 red bits and this red bit here, we get this. Now if you were asked to describe this as a fraction, it would be very wise to say that this was three quarters. Looking at the numerical version of the sum, you can see that the denominator, the number on the bottom of the fraction has stayed the same. It is only the numerators which have been added together to give the final answer. 2 plus 1 equals 3. So two quarters plus one quarter equals three quarters. Let's look at one more example. This time, let's not use diagrams Let's look at four elevenths plus two elevenths. Now remember, the denominator is unaffected and stays the same. Here we only add the numerators. 4 plus 2 is 6 and this gives us six elevenths. Subtracting fractions is exactly the same method. Let's subtract five sevenths and let's subtract from that three sevenths. All we need to do is once again we keep the denominator the same. And here we subtract 3 from 5 and this gives us 2. Let's look at a quick example with diagrams to show us how that works. This time, let's subtract one quarter from two quarters. Now as you can see in the diagram, we have these two and we take away this one, we're left with just this quadrant.which means we're left with one quarter which is 2 minus 1 quarter. And that's how to add and subtract fractions with the same denominator.
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