**Year 3 Maths – Count up and down in tenths** *KS2 Revision*

## What you need to know

**Things to remember:**

- When we count up and down in tenths, it is like counting normally, we just have a 10 on the bottom of a fraction!
- Because the number on the bottom doesn’t change when we add fractions, we can put our hand over it so it doesn’t distract us.

Before starting, here are some fancy words for the names of the number in a fraction.

\frac{2}{10} \hspace{1em} \frac{\leftarrow Numerator}{\leftarrow Denominator}

If you look carefully, a fraction is just a big division symbol. The numerator is what we are dividing, and the denominator is what we are diving by (or the number of pieces we are cutting something into).

\frac{1}{10} \hspace{1em}\frac{2}{10}\hspace{1em}\frac{3}{10} \hspace{1em}\frac{4}{10} \hspace{1em}\frac{5}{10} \hspace{1em}\frac{6}{10} \hspace{1em}\frac{7}{10} \hspace{1em}\frac{8}{10} \hspace{1em}\frac{9}{10} \hspace{1em}\frac{10}{10}

** **

Looking at our tenths in order, we can see two key points:

1. The numbers on top go up like they do normally when we count in 1s.

2. The numbers on the bottom, the 10s, don’t change.

So, really, we can count up and down in tenths how we would normally, we just need to remember the 10s on the bottom!

So, how could we find the missing number in this list?

\frac{3}{10} \hspace{1em}\frac{4}{10}\hspace{1em}\frac{5}{10} \hspace{1em}\frac{}{10} \hspace{1em}\frac{7}{10}

To find the missing number, we know that all we have to do is count up as usual… 3… 4… 5… 7… Well, we know that the number between 5 and 7 is 6, so our missing number is a 6!

## Example Questions

**Question 1: **Find the missing number in:

\frac{2}{10} \hspace{1em}\frac{}{10}\hspace{1em}\frac{4}{10} \hspace{1em}\frac{5}{10} \hspace{1em}\frac{6}{10}

Count up as we usually do: 2… 4… 5… 6… We can see that the missing number will be a 3!

**Question 2**: Find the number in:

\frac{9}{10} \hspace{1em}\frac{8}{10}\hspace{1em}\frac{7}{10} \hspace{1em}\frac{}{10} \hspace{1em}\frac{5}{10}

Notice how this time you need to count down: 9… 8… 7… 5… We can see that the missing number will be a 6!