Fractions with objects (2,3,4,5)

We have looked at fractions on fraction bars, fractions on a number line and fractions of shapes. However, fractions can also be used to divide a collection of items. To do this we use the:

• denominator to divide the items into equal groups
• numerator to select the number of groups

Let's watch a video to learn more:

 

Unit fractions

When we only select one of the groups (so the numerator is one) it is called a unit fraction.

For example, to find $\frac{1}{4}$14​ of $20$20 items, we divide the collection into four equal groups ($5$5 in each group) and then select one of them. Like this:

Try this question for yourself:

Worked example

Question 1:

 

Non-unit fractions

We can also select more than one group which we would write as a non-unit fraction. This is where the numerator (top number) is larger than $1$1.

For example, to find two thirds ($\frac{2}{3}$23​) of $12$12 items, we use the denominator to divide the items into equal groups (three equal groups) and then we select two of the groups.

Like this:

 

When we divide the twelve boats into three equal groups, there are four in each group. We then select two of the groups, eight boats, to represent two-thirds. Therefore, $\frac{2}{3}$23​ of $12=8$12=8

Try this question for yourself:

Worked example

Question 2: