This series of 3 minute math is designed as a quick reminder for some of the main topics. I hope they help to provide a focus and a way forward. If you need any more detail please search the site or contact me – always pleased to answer any questions!
All the very best with your studies.
Transcript from the video:
“In this series we're going to start looking at three minute math and this video is all about ‘how to add fractions'.
The first thing to know about adding fractions is that you need to make sure that the denominator, which is the number on the bottom, is the same for all the fractions in the sum. This makes it fairly straight forward. If you have something like:
you just simply add the two fractions together – so three plus one =
The next thing you need to remember is that, when you're dealing with fractions, you need to make them as small as possible. In this example we can divide the top number by four and the bottom number by four:
.. and the answer to this question.
Now let's say that the question that you're presented with also has whole numbers in it. It might be something like:
all we need to do is add the two whole numbers together and we get seven. Next, we add . We then reduce this so that it becomes .
When the denominators (which is the numbers on the bottom) are the same the sum is fairly straight forward. This time, we'll consider:
We need to make the denominators the same.
To do this, I am going to convert them to something over twelve plus something over twelve.
Firstly, three times four is twelve, so therefore I multiply the top by four – four times two is eight. Next, four times three is twelve so I multiply one by three which gives me three.
Now I have
In terms of a typical exam paper you're probably going to get something like:
The way to handle this is to add the two integers together (the whole numbers) which gives 9, then add the two fractions together and you get .
That's pretty much all there is to adding fractions! The only other thing that you need to remember is occasionally you might use this method and you'll end up with an answer something like:
This fraction just needs a little bit of tidying up and what we do is convert some of those elevenths into a whole number which gives us .
In a typical exam paper you're more likely to get a fraction question with whole numbers and mixed denominators so you always need to make sure that the denominators are the same – in this particular case, we had twelfths.
I hope that's been helpful and I look forward to seeing you inside the next three minutes.”
Watch video on YouTube – 3 Minute Math – Adding Fractions
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