Number lines – up to 100
key notes :
What is a Number Line?
A number line is like a straight road for numbers! It helps us see numbers in order, from smallest to biggest. Imagine it as a ruler that goes on and on!
Number lines help us with:
- Counting
- Adding
- Subtracting
How to Use a Number Line
- Find Your Starting Number: Look for the number you want to start with on the line.
- Counting Up (Adding): To add, move to the right along the number line. Each jump is +1!
- Counting Down (Subtracting): To subtract, move to the left along the number line. Each jump is -1!
Number Line Examples (Up to 100)
Let’s see some examples:
Example 1: Counting from 20 to 30
Imagine a number line. Start at 20. Count each line until you reach 30.
Example 2: 45 + 5 = ?
Start at 45. Then, jump 5 spaces to the right. Where do you land? You land on 50! So, 45 + 5 = 50
Example 3: 78 – 8 = ?
Start at 78. Then, jump 8 spaces to the left. Where do you land? You land on 70! So, 78 – 8 = 70
Number lines can also count by 2s, 5s or 10s!
When you jump by 2, it’s like saying 2, 4, 6, 8 etc.
When you jump by 5, it’s like saying 5, 10, 15, 20 etc.
When you jump by 10, it’s like saying 10, 20, 30, 40 etc.
Tips for Using Number Lines
- Always start at the correct number.
- Make clear jumps.
- Double-check your counting!
Learn with an example
🔴 Type the missing number.
Find the number that comes between 54 and 56. You can start at 53 and count up.
55 comes between 54 and 56.
🔴 Which number comes just before 53?
First, find 53 on the number line.
Now find which number comes just before 53. Look one number to the left on the number line.
52 comes just before 53.
🔴 Which number comes just after 58?
First, find 58 on the number line.
Now find which number comes just after 58. Look one number to the right on the number line.
59 comes just after 58.
Let’s practice!
