Fractions - Learning how to add.
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Adding fractions is really easy once you have the same denominator for all the fractions you want to add. Take a look at the example below. Notice that all you have to do is add the numerators together (the top number). The denominator (the bottom number) remains the same. Of course now you should write the correct equivalent fraction 1/2 (half)
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Now add fractions with different denominators, this is slightly harder, but if you know your multiplication tables then it can be fairly quick to work them out. We’ll go through an example, an easy one to start, one that you may already know the answer to.
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The fraction picture above shows that the answer is correct, but how do you add fractions mathematically?
Remember learning about equivalent fractions? This is why you learnt them! You need to change the fractions so they have the same denominator (bottom number)
That question was easy wasn’t it! Let’s try something harder, just to make sure you’ve got the idea.
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To add the fractions you need to work out which denominator (bottom) to use. You must use ten. (I’ll explain why later).
Now, how many fives make ten? Two. So If you multiply the denominator by two you must multiply the numerator by two. So two times two is four
THE GOLDEN RULE: What ever you do to the top, you must do to the bottom. In this case you multiplied by two.
 
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If you had tried to use five as the denominator (bottom) you would have got stuck, take a look at the example below. When you divide three by two you get one and a half. This is called a complex fraction and you don’t use complex fractions for addition or at this level.
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Looking for fraction worksheets? You might find some in the links below.
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