Find the Missing Number on a Number Line
Basics on the topic Find the Missing Number on a Number Line
Missing Numbers on a Number Line
Number lines are really helpful tools that we can use in maths, however, sometimes we might come across a number line with missing numbers! We need a missing numbers on a number line strategy to work out how to write the missing numbers for each number line! Watch this video to learn more about how to find missing addends with a number line and then have a go at out missing numbers on a number line worksheet to practise!
How Do You Find the Missing Number on a Number Line?
Let’s have a look at the definition of a number line:
A number line is a diagram in which numbers are represented as points on a line. They count by a specific number, sometimes in ones, twos, fives or even tens.
But, what happens when a number is missing? Follow these steps and learn how to fill in missing numbers on a number line:
Step #  What to do 

1  Look at the whole number line. 
2  Look for the number line pattern – What the number line is counting in. 
3  Count using this pattern to find the missing number on the number line pattern. 
4  Reread the number line to make sure it is correct. 
Missing Numbers on Number Lines – Practice
How can you figure out missing numbers using patterns on a number line? Let’s practice filling in missing numbers on a number line! Our number line includes numbers from 35 to 70.
Can you figure out which numbers are missing from this number line? Remember our steps to find missing numbers on number lines.
Let’s look at this number line with missing numbers, what is the pattern? The pattern shows incremental steps of +5! Knowing this, we can figure out the missing numbers by counting on five from the last known number. This number line is missing the numbers fortyfive and fiftyfive!
Missing Numbers on a Number Line KS1 – Summary
When finding missing numbers on a number line;
First: look at the whole number line.
Then: look for the missing number line pattern – what the number line is counting in.
Next: count using this pattern to find the missing number!
Finally: reread the number line again to make sure it is correct.
Do you want to have a go at some missing number line problems? After watching this video, check out the interactive exercises and have a go at our fill in the missing numbers on the number line worksheets.
Find the Missing Number on a Number Line exercise

What are the steps of finding a missing number on a number line?
HintsThe image provides an example of the first step of finding a missing number on a number line.
What do you need to do next? Look at the first part of this number line for a clue.
In this example, we have looked at the whole number line and found out it is counting in steps of one. We can now count up in ones to find the missing numbers.
SolutionHere are the steps in the correct order:
 First, look at the whole number line.
 Look for the pattern or what the number line is counting in.
 Count using this pattern to find the missing number or numbers.
 Reread the number line again to make sure it is correct.

Which numbers are missing?
HintsWhat is the pattern counting in?
Here is an example of counting in steps of ten:
20, 30, 40, 50
What comes after 60 when counting in tens?
What comes after 90 when counting in tens?
SolutionThe number line counts in steps of ten.
 The missing numbers are 70 and 100.

Help Skylar and Henry find the trail.
HintsLook at the whole number line. What is it counting in?
Here is an example of counting by steps of five:
15, 20, 25, 30
What comes after 65 when counting in fives?
What comes after 80 when counting in fives?
SolutionThe number line counts in steps of five.
 The missing numbers are 70 and 85.

Missing numbers.
HintsWhat is the pattern counting in?
Look where there are two numbers next to each other and find the difference between these two numbers.
For example, if we were completing:
13, ?, 15, 16
We could look and see there is only one between 15 and 16 so the number line must be counting in steps of one. We can then fill in the number 14 as that is one more than 13.
Solution 15, 20, 25, 30, 35, 40, 45. The number line is counting in steps of five.
 24, 25, 26, 27, 28, 29, 30. The number line is counting in steps of one.
 0, 10, 20, 30, 40, 50, 60. The number line is counting in steps of ten.

Can you complete the number line?
HintsThe first step when a number is missing on a number line, is to look at the whole number line.
The second step is to look for the pattern or what the number line is counting in.
The third step is to count using this pattern to find the missing numbers.
The fourth step is to reread the number line again to make sure it is correct.
SolutionThe number line counts in steps of one.
 The missing numbers are 46, 49, and 51.

Number line patterns.
HintsHere is an example of counting in steps of one:
12, 13, 14, 15
Her is an example of counting in steps of two:
2, 4, 6, 8, 10
Here is an example of counting in steps of five:
50, 55, 60, 65
Here is an example of counting in steps of ten:
40, 50, 60, 70
SolutionSteps of one.
 59, 60, ?, 62, 63, 64, 65
 The missing number is 61.
Steps of two.
 12, 14, 16, ?, 20, 22
 The missing number is 18.
Steps of five.
 25, ?, 35, 40, 45
 The missing number is 30.
Steps of ten.
 80, 90, ?, 110, 120, 130
 The missing number is 100.