Short instructional video (transcript) by Rob Langman on converting between proper fractions and decimals. Teachers use 100-grids and place-value language (tenths, hundredths) to show equivalence: e.g., 0.2 = 2/10; 0.36 = 36/100 = 9/25; converting 3/5 to tenths gives 6/10 → 0.6. The clip includes teacher prompts for pupils and notes that the method works best when denominators are factors or multiples of 10 or 100.
Chapters
Hi, I'm Florence, and today we're going.
To look at converting between proper fractions and decimals.
So remember that the place value in our decimals refers to fractions already, tenths and hundredths. But you can explore what a decimal.
Like this looks like as a fraction.
By using 100 grid or square to represent a whole. So here in my decimal, I have no holes and two tenths, so I'm going to shade in two out of the ten equal parts of my whole. Pupils can then really clearly see that I've shaded 2 out of 10 equal parts. So 0.2 is a fraction, is 2/10.
And if you want to challenge them.
Further, then you could ask them, how.
Many hundredths have we shaded in?
And they should be able to see we've shaded ten, twenty out of a possible hundred. So two tenths is the same as twenty hundredths. In this example, we've got tenths and hundredths, but we can use the same strategy. So I'm going to shade three tenths and then I need to shade six hundredths. And again, pupils should be able to see that 0.36 is 10, 20, 31, 2, 3, 4, 5, 36 out of 100 equal parts, And hopefully they'll recognize that we can simplify that fraction further to 9/25. So in this last example, we've got.
A fraction, we need to express it as a decimal.
And I start off by asking pupils.
To consider how we could do this.
Is there anything that they've learned before.
That they could use to help them?
Hopefully, they'll recognise that our denominator is.
A factor of 10.
So we can convert 3/5 into 10ths.
Which makes it much easier to express as a decimal.
If we make our denominator 10, it means that we've multiplied it by two. And knowing what we know about equivalence, whatever we do to our denominator, we also need to do the same to the numerator. So three multiplied by two is going to give us six tenths, and we can write that as a decimal as 0.6. This can also work in some instances.
When your denominator is a multiple of 10 or 100.
So here pupils should recognise they can use equivalents again, but this time they will divide to make it the denominator into tenths, 4/10, meaning we can write it as 0.4.
So there you go.
That's how pupils can begin to convert.
Between proper fractions and decimals. This method doesn't work for all fractions.
But it's a really good starting point for your pupils.
