5. Fractions

Lesson

Let's try this problem to review how to identify a fraction of a group of objects.

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

A

B

C

Worked Solution

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.

This video looks at finding a unit fraction of a quantity.

What is \dfrac15 of 20?

Worked Solution

Idea summary

We can quickly find the unit fraction of a whole number by dividing the whole number by the denominator.

This video looks at finding a non-unit fraction of a quantity.

What is \dfrac{6}{11} of \$55?

Worked Solution

Idea summary

You can find a fraction of an amount by:

Dividing the total quantity by the denominator, then multiplying the answer by the numerator, or

Multiplying the total quantity by the numerator, then dividing the answer by the denominator.

Find a simple fraction of a quantity where the result is a whole number, with and without digital technologies