This worksheet is about
number composing and decomposing up to 10. The goal is to
decompose the whole number into two parts (addends) so that they add up to the total (the "whole"). Each diagram shows a large circle (representing the whole number) connected to two smaller circles (representing the parts). One or both of the small circles may be missing a number, and you need to
find the missing part.
Let’s go through each one step by step:
---
🔹 1. First Row – Left
- Whole:
1
- One part:
0
- Missing part: ?
We know:
> 0 + ? = 1
So, ? =
1
✔ Answer:
1
---
🔹 2. First Row – Right
- Whole:
7
- One part:
2
- Missing part: ?
We know:
> 2 + ? = 7
So, ? =
5
✔ Answer:
5
---
🔹 3. Second Row – Left
- Whole:
9
- One part:
3
- Missing part: ?
We know:
> 3 + ? = 9
So, ? =
6
✔ Answer:
6
---
🔹 4. Second Row – Right
- Whole:
10
- One part:
2
- Missing part: ?
We know:
> 2 + ? = 10
So, ? =
8
✔ Answer:
8
---
🔹 5. Third Row – Left
- Whole:
5
- One part:
4
- Missing part: ?
We know:
> 4 + ? = 5
So, ? =
1
✔ Answer:
1
---
🔹 6. Third Row – Right
- Whole:
6
- One part:
3
- Missing part: ?
We know:
> 3 + ? = 6
So, ? =
3
✔ Answer:
3
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✔ Final Answers:
| Diagram | Missing Number |
|--------|----------------|
| 1 | 1 |
| 2 | 5 |
| 3 | 6 |
| 4 | 8 |
| 5 | 1 |
| 6 | 3 |
---
💡 Explanation:
This activity teaches
number bonds — how numbers can be broken down into smaller parts. For example:
- 1 = 0 + 1
- 7 = 2 + 5
- 9 = 3 + 6
- 10 = 2 + 8
- 5 = 4 + 1
- 6 = 3 + 3
It helps children understand addition and subtraction as inverse operations and builds mental math skills.
You can fill in the blank circles with these answers! 🎉
Parent Tip: Review the logic above to help your child master the concept of decompose worksheet.
