 # 4.03 Fractions of objects

Lesson

## Ideas

Do you know how to find a fraction of a  collection of objects  ?

### Examples

#### Example 1

Which of the following shows that \dfrac{1}{2} of these flowers have been selected?

A
B
C
Worked Solution
Create a strategy

Count the number of flowers and halve it.

Apply the idea

There are 16 flowers. Half of 16 is 8.

Option C has 8 flowers circled, so option C is the answer.

Idea summary

To find a fraction of an amount, use the:

• denominator (bottom number) to divide the items into equal groups.
• numerator (top number) to select the number of groups.

## Fractions of collections

This video looks at how to use fractions to divide up a group of objects.

### Examples

#### Example 2

Which of the following shows that \dfrac{3}{4} of these ice creams have been selected?

A
B
C
Worked Solution
Create a strategy

Find what \dfrac{1}{4} of the ice creams would look like and choose the option that shows 3 of the 4 equal groups.

Apply the idea

Here is 1 quarter of the ice creams. We can see that 1 quarter of the ice creams means 3 ice creams.\dfrac{1}{4}\text{ of the ice creams }=3

So 3 quarter means 3 of the 4 groups. 3 lots of 3 is 9.\begin{aligned} \dfrac{3}{4} \text{ of the ice creams } &= 3 \times 3 \\ &= 9 \end{aligned}

So the correct answer is Option B because it shows 9 ice creams selected from 12 ice creams.

Idea summary

The denominator tells us the number of equal parts that we need to divide the collection of objects into.

The numerator tells us the number of equal parts that we need to select to represent our fraction.

To find a fraction of a collection, we can first find the unit fraction of the collection, then multiply it so that we get the desired fraction.