We’re updating Ivy Maths.We apologise for any bugs while we make improvements. Thanks for your patience.
All topics
Year 1 · Addition and subtraction
Work out a missing part when the whole is known
Definition
Subtraction takes one amount away from another, or finds the difference between two numbers. It is the inverse of addition, each operation undoes the other.
Why Do I Have to Learn This?
Subtracting tells you what is left, what has changed, and how far apart two numbers are. You use it every time you spend money or count down to something.
Key Rules:
- 1. Subtracting cannot be done in any order: 8 − 3 is not 3 − 8.
- 2. Subtraction is the inverse of addition, so you can check a subtraction by adding back.
- 3. Exchange one ten for ten ones when a column does not have enough to take away.
Remember:
- •A number line makes "how far apart" questions visible, count the jumps.
- •When subtracting, exchange rather than "borrowing" and forgetting to pay it back.
- •Finding the difference and taking away are the same operation asked two ways.
Difference
The result of a subtraction, a − b: how far apart two numbers are.
The difference between 10 and 6 is 4.
Animated Example:
0 + 9 = 9
Free Work out a missing part when the whole is known Worksheet
Download free worksheets and practise today.
Every download has a fresh set of questions.
Let’s Practise the Concept
Step 1 of 3
Put them in order
Tap the numbers from smallest to largest.
In order so far: nothing yet