Adding fractions

June 27, 2024•2 min read

In their simplest form they seem fairly harmless.
They lull you into this false sense of security. Then they reveal their true colours!

Fractions seem to be something that confuse a lot of people.

In their simplest form they seem fairly harmless.

They lull you into this false sense of security. Then they reveal their true colours!

Adding fractions when they have the same denominator (bottom number) is straightforward. The bottom number stays the same, you just add the digits on the top.

So, 2/5 + 1/5 = 3/5

The same applies when you need to subtract: 2/5 - 1/5 = 1/5

Then once they have convinced you of how nice they are, they turn out to be quite spiteful!

If the denominator differs, we need to make them the same before we can continue. We have 2 options.

Option one: 2/5 +7/10

Because 5 is a factor (a number that goes into another number without leaving any remainders/mess behind) we can just double the 5.

We would then need to double the 5 as well to keep the fractions equivalent.

This would give us: 4/10 + 7/10 Now we can add the top numbers together and keep the 10 the same giving us 11/10.

However, sometimes they will give you something much harsher!

They might present you with something like: 4/5 + 2/3

The first thing to do is to multiply the bottom numbers together so that we have a common denominator.

5x3 = 15

At this point I normally rewrite the question but just put the 15s at the bottom of the fraction. Nothing else:

+ =

15 15 15

Because I multiplied the 5 by 3 to get to 15, I need to multiply the 4 by 3 as well to keep them equivalent.

This would give me 12. I can now place this on top of the first fraction:

14 + =

15 15 15

Now because I multiplied the 3 by 5 to get to 15, I must multiply the 2 by 5 as well. 2x5= 10 This now sits on top of the second fraction:

14 + 10 =

15 15 15

Finally, keeping the 15 the same, I can add the 14 and the 10 together to get my final answer: 24/10

I rewrite the fraction first with the new denominator so that I’m not tempted to add them together as well.

This was very much adding fractions in a nutshell, but I hope it helps.

$adding fractions with different denominators$

Dawn Strachan

For the past 20+ years I have been a firm believer that learning should be an enjoyable experience. I appreciate that traditionally education has revolved around worksheets, textbooks, listening to teachers. But a grounding in early years and working with children who had a variety of learning styles from I learned that it is an individual activity that is personal to all of us. We don’t all learn in the same way. Our influences, our experiences, our capabilities all influence how we retain information. But through it all, I believe that if we can make it enjoyable and engaging, they will want to participate. With participation comes practice which in turn boosts skill and confidence. With an increase in skill and confidence comes a willingness to have a go. This in turn leads to more practice which leads to a positive spiral of success. The moral, we need to make learning fun, engaging, use a range of techniques.

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