➡️ Number Lines
A number line is a straight line with numbers in order. We can use it to count, add, and subtract!
➡️ What is a Number Line?
A number line shows numbers placed in order from smallest to largest, left to right. Numbers get bigger as you move right, and smaller as you move left.
Moving RIGHT = counting ON (adding)
Moving LEFT = counting BACK (subtracting)
📍 Placing Numbers on a Number Line
To place a number, find where it belongs between the marked numbers. Think about whether it is closer to the smaller or larger marked number.
Where does 35 go on a number line from 0 to 50?
35 sits halfway between 30 and 40.
➕➖ Operations on a Number Line
We can use jumps on a number line to add or subtract. Each jump of 1 moves one space.
Adding: 24 + 5 = ?
Start at 24. Jump forward 5 spaces: 25, 26, 27, 28, 29. Answer: 29
Subtracting: 37 − 4 = ?
Start at 37. Jump back 4 spaces: 36, 35, 34, 33. Answer: 33
Worked Examples
Example 1: Where does 47 go?
On a number line from 40 to 50, where does 47 sit?
47 sits 7 spaces past 40 — closer to 50 than to 40. ✅
Example 2: 52 + 6 on a number line
Start at 52, jump forward 6: 53, 54, 55, 56, 57, 58.
52 + 6 = 58 ✅
Example 3: 64 − 7 on a number line
Start at 64, jump back 7: 63, 62, 61, 60, 59, 58, 57.
64 − 7 = 57 ✅
Key Vocabulary
A straight line with numbers placed in order.
To jump forward (right) on the number line — this is adding.
To jump backward (left) on the number line — this is subtracting.
The gap between two numbers on a number line.
Knowledge Check
Question 1: On a number line from 0 to 100, which number is exactly halfway?
Question 2: Use a number line. What is 33 + 5?
Question 3: Use a number line. What is 45 − 3?
Question 4: On a number line, which direction do you move to subtract?
Question 5: Use the number line. What number is 6 jumps forward from 74?
Pax Says:
"Draw your own number line on paper! Put 0 on the left and 20 on the right, then mark every number in between. Try jumping forward and back!"
Key Concepts Summary
- ✓ A number line shows numbers in order from left (small) to right (large).
- ✓ Jumping RIGHT means adding (counting on).
- ✓ Jumping LEFT means subtracting (counting back).
- ✓ Numbers can be placed between marked points on the number line.