Grade 3 Mathematics Numbers – Missing Numbers Notes
Mathematics — Numbers
Subtopic: Missing Numbers (Age 8 — Kenya)
What are missing numbers?
Missing numbers are numbers that are left out from a number sequence. You find them by seeing the pattern or counting on a number line.
How to find missing numbers
- Look at the numbers and see how they change: do they go up or down? By 1? By 2? By 5?
- Use a number line to count forwards or backwards.
- Check your answer by counting again or doing the opposite (if you added 2, subtract 2 to check).
Simple examples
Example 1 — Count by 1s:
4
?
6
We see numbers go up by 1 → 4, 5, 6. So ? = 5.
Example 2 — Count by 2s:
10
?
14
10 → 12 → 14, so ? = 12.
Use a number line:
7
8
?
10
Count forward 7 → 8 → 9 → 10, so ? = 9.
Patterns you will meet
- Counting by 1s: 1, 2, 3, 4, …
- Counting by 2s: 2, 4, 6, 8, …
- Counting by 5s: 5, 10, 15, 20, … (use your fingers or Kenyan coin examples)
- Counting by 10s: 10, 20, 30, …
Practice — fill the missing numbers
- 3, __, 5
- __ , 11, 12
- 14, __, 16
- __ , 6, 8
- 10, __, 30 (count by tens)
- 5, __, __, 20 (count by 5s)
- __ , 17, __ , 15 (count down)
- 7, __, 9, __, 11
- __ , 2, 4, __ (count by 2s)
- 20, __, 18
A short activity (Kenyan context)
Maria has these coins: 5 sh, 10 sh, __ , 20 sh. Count by 5s to find the missing coin. (Answer: 15 sh)
Homework ideas
- Ask a parent to write number sequences with gaps for you to fill.
- Use a chalk on the ground to draw number lines and jump as you count.
- Practice counting Kenyan coins or notes in order to see real-life patterns.
Remember: Missing numbers are found by spotting the pattern or counting on a number line. Always check your answer by counting again.