Year 5 - Maths
Find the whole when the size of a unit fraction is known
Find unit and non-unit fractions of whole numbers exploring parts and wholes
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit pupils will find unit and non-unit fractions of whole numbers and explore parts and wholes.
Lesson Summary
You will learn to find the whole when the size of a unit fraction is known.
Key Notes
- The whole has been divided into __ equal parts and this is one of the parts.
- There will be __ of these parts in the whole.
- The whole is __ times the size of this part.
- If you know the size of a unit fraction, you can work out the size of the whole.
Vocabulary To Learn
- Unit fraction: A unit fraction is a fraction that has a numerator of one.
- Denominator: The denominator is the number on the bottom of a fraction. It tells us how many parts the whole has been divided into.
Common Mistakes To Avoid
- When a unit fraction is represented as a quantity greater than one, pupils may think each part of the unit fractions quantity is itself the unit fraction of the whole.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
The whole has been divided into __ equal parts and this is one of the parts. There will be __ of these parts in the whole.
2. Use this key word in a maths sentence and explain it clearly. 'Unit fraction'
A unit fraction is a fraction that has a numerator of one. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: When a unit fraction is represented as a quantity greater than one, pupils may think each part of the unit fractions quantity is itself the unit fraction of the whole. Correction: Draw a circle around the quantity each time to encourage pupils to recognise that each set of objects is representative of a quantity that is one part of the whole.
More Lessons In This Unit
- Explain how dividing by a whole number relates to multiplying by a unit fraction Study Guide
- Explain how finding a fraction of a quantity relates to multiplying by a unit fraction Study Guide
- Explain when a calculation represents scaling down and when it represents repeated addition Study Guide
- Find a non-unit fraction of a quantity using mental and written calculation strategies Study Guide
- Find a unit fraction of a quantity using representations Study Guide
- Find a unit fraction when the size of a non-unit fraction is known Study Guide
- Find the whole when the size of a non-unit fraction is known Study Guide
- Multiply a whole number by a proper fraction Study Guide
- Use knowledge of multiplying a whole number by a unit fraction to solve problems Study Guide
Browse all guides in the Year 5 Maths guide library.