Year 2 - Maths
Use knowledge of facts and unitising to add and subtract multiples of ten
Composition of multiples of 10
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 represent multiples of ten using numerals and names and use knowledge of facts and unitising to add and subtract multiples of ten.
Lesson Summary
You will learn to use knowledge of known facts and unitising to add and subtract multiples of ten.
Key Notes
- Tens numbers can be added to or subtracted from a multiple of ten.
- When you add a tens number to a multiple of ten the tens number increases.
- When you subtract a tens number from a multiple of ten the tens number decreases.
- If 3 + 1 is equal to 4 then 3 tens + 1 ten is equal to 4 tens which is equal to 40
- If 4 - 1 is equal to 3 then 4 tens subtract 1 ten is equal to 3 tens which is equal to 30
Vocabulary To Learn
- Add: To find the total, or sum, by combining two or more parts (addends), or to increase an amount by adding another.
- Plus: To find the total, or sum, by combining two or more parts (addends), or to increase an amount by adding another.
- Subtract: To partition one part from another (the subtrahend from the difference), or to decrease an amount by taking an amount away.
- Minus: To partition one part from another (the subtrahend from the difference), or to decrease an amount by taking an amount away.
Common Mistakes To Avoid
- Children may use counting on and back strategies instead of application of known facts and therefore be inefficient when adding and subtracting multiples of 10
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
Tens numbers can be added to or subtracted from a multiple of ten. When you add a tens number to a multiple of ten the tens number increases.
2. Use this key word in a maths sentence and explain it clearly. 'Add'
To find the total, or sum, by combining two or more parts (addends), or to increase an amount by adding another. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Children may use counting on and back strategies instead of application of known facts and therefore be inefficient when adding and subtracting multiples of 10. Correction: Use representations to make clear links when unitising e.g. adding 2 to 3 and then adding 2 groups of 10 to 3 groups of 10, to support children in making the link. Children should be increasingly fluent in addition and subtraction within 10.
More Lessons In This Unit
- Add and subtract multiples of ten Study Guide
- Estimate the position of multiples of ten on a 0 - 100 number line Study Guide
- Explain that one ten is equivalent to ten ones Study Guide
- Explain what happens when you add and subtract ten to a multiple of ten Study Guide
- Represent multiples of ten in an expression or an equation Study Guide
- Represent multiples of ten using their numerals Study Guide
- Represent multiples of ten using their numerals and names Study Guide
- Solve problems involving multiples of ten Study Guide
- Solve problems involving multiples of ten in a range of contexts Study Guide
Browse all guides in the Year 2 Maths guide library.