Subtraction of Numbers — Grade 1 Mathematics
Subtraction is all about taking away. When we subtract, we start with a group of things and remove some of them to find out how many are left. It is the opposite of addition — and just as important!
Understanding Subtraction
Subtraction means removing part of a group and finding what is left over (the difference).
We use the minus sign (−) to show we are taking away, and the equals sign (=) to show the answer.
A subtraction number sentence looks like:
9 − 4 = 5
— which reads "9 minus 4 equals 5" or "if I take 4 away from 9, I have 5 left."
We use the minus sign (−) to show we are taking away, and the equals sign (=) to show the answer.
A subtraction number sentence looks like:
9 − 4 = 5
— which reads "9 minus 4 equals 5" or "if I take 4 away from 9, I have 5 left."
💡 Tip: Subtraction and addition are opposites. If 6 + 3 = 9, then 9 − 3 = 6 and 9 − 6 = 3. Use addition to check your subtraction!
Worked Examples
Example 1 — Number Format
Work out 10 − 6. Start at 10 and count back 6.
10 − 6 = 4
- Start at 10.
- Count backwards 6 steps: 9, 8, 7, 6, 5, 4
- We land on 4. The answer is 4.
Example 2 — Real World Scenario
There are 8 birds 🐦 sitting on a fence. Then 3 fly away. How many birds are still on the fence?
🐦🐦🐦🐦🐦🐦🐦🐦
3 birds fly away → 🐦🐦🐦
🐦🐦🐦🐦🐦
8 − 3 = 5 birds still on the fence
Example 3 — Subtraction on a Number Line
Solve 12 − 5 by starting at 12 and jumping back 5 spaces.
7
8
9
10
11
12
12 − 5 = 7
Start at 12 (orange), jump back 5 steps to land on 7 (orange).
Practice Questions
Try these! Work out the answers first, then check.
1. What is 9 − 4?
✅ 9 − 4 = 5
2. There are 15 grapes 🍇. You eat 7. How many are left?
✅ 15 − 7 = 8 grapes remaining.
3. What is 20 − 8?
✅ 20 − 8 = 12
4. Find the missing number: 14 − ___ = 6
✅ 14 − 8 = 6
5. Check with addition: Is 11 − 4 = 7? How do you know?
✅ Yes! Because 7 + 4 = 11. ✔
Key Points to Remember
- Subtraction means taking away to find what is left.
- We use the symbol − (minus) and = (equals).
- You cannot swap the order in subtraction: 9 − 4 ≠ 4 − 9.
- Use a number line and count backwards to subtract.
- Check your subtraction using addition — they are opposites!