Lesson video

Hi, I'm Mr. Chung.

And in this lesson, we're going to learn about changing percentages to fractions and decimals.

Let's begin with a recap of what percentages and the different ways we can represent the percentage pictorially.

So in our first diagram, we have 100 Square that's a 10 by 10 grid, we can see that.

Where we have, I can see 49 squares shaded out of 100.

So if I think about that as 49 hundredths that would be a percentage of 49%.

In our second diagram, we have a number line from zero to one.

where the bar goes across, up to 0.

9.

So that would be nine tenths.

So nine tenths is an equivalent fraction to 90 hundredths.

So I can say that that's 90%.

So if I know whole one is 100% in our third representation percentage.

I have the number shown there as 2.

42.

So the two whole ones would represent 200%.

And the point four two part would be 42%.

So in total there, I have 242%.

Here's some representation of percentage questions you can try.

Pause the video to have a go, resume the video once you're finished.

Here the answers.

How did you get on? It's important that these representations of percentages you count really carefully.

Particularly in those hundred squares, and in those place value counters.

Hopefully you got them all correct.

So let's look at converting each percentage to a fraction and decimals.

So we're going to begin with 49%.

49%, because it's a percentage already I know it's 49 hundredths.

Now 49 hundredths is simply 0.

49.

Think about either 49 divided by 100 or 49 in the hundredths column, which would be 0.

49.

Moving on to the 90%.

I know 90% would be 90 hundredths, which simplifies to nine tenths by dividing the numerator and denominator by 10.

Nine tenths simply means 0.

9.

So I there have 90% as a decimal.

So 242%, I can think of is 242 out of 100.

Which then simplifies to 121 fiftieth as a fraction and because it's two hundred and forty two hundredths as a decimal it will be 2.

42.

Here's some questions for you to try.

Pause the video to complete the task.

Resume the video once you're finished.

Here are the answers.

Remember the important thing about percentage, is it's a representation of number out of 100.

So if we take 25% as an example, that means it's 25 out of 100.

Which simply also means 25 divided by 100.

25 hundredths simplifies to one quarter.

And also as a decimal 25 divided by 100 means 0.

25.

Here's some more questions for you to try.

Pause the video to complete the task.

Resume the video once you're finished.

Here are the answers.

Wow, some really amazing facts here.

85% of plant life is found in the ocean.

That's a 17th 20th of plant life.

Cucumbers are 96% water.

That's a fraction of 24 after 25.

Hopefully you got all these correct.

Here's more questions for you to have a go at.

Pause the video, complete the task.

Resume the video once you're finished.

Here are the answers.

So if you look at question four, Simon's incorrect because 3% does not equal 0.

3.

You can see the working out there in the answers to say why he's incorrect.

But that's quite a common mistake.

So let's hope that you don't make that mistake.

That's all for this lesson.

Thanks for watching.