- A number line shows the increasing order of arrangement of numbers.
- It has arrow ends on both the sides since the numbers has no starting and ending number.
- The center number of a number line is always 0.
- 0 is called as the origin of the number line.
- The numbers to the right of 0 are called positive numbers.
- The numbers to the left of 0 are called negative numbers.
- We could represent all the real numbers in the number line
- Number lines are useful in doing addition and subtraction.
General Representation of Number Line
Always the number line wont be in the order 0, 1, 2, 3...
Sometimes it would be 0, 5, 10, 15...
or 10, 20, 30, 40...
or 100, 200, 300, 400...
Types of Number Lines
Number line using multiple of 2.
<------|-----|------|------|------|------|------|------|------|------|------|------>
0 2 4 6 8 10 12 14 16 18 20
Number line using multiple of 5.
<------|------|------|------|------|------|------|------|------|------|------|------>
0 5 10 15 20 25 30 35 40 45 50
Number line using multiple of 10.
<------|------|------|------|------|------|------|------|------|------|------|------>
10 20 30 40 50 60 70 80 90 100 110
Number line using multiple of 20.
<------|----|------|------|------|------|------|------|------|------|------|------>
0 20 40 60 80 100 120 140 160 180 200
Number line using multiple of 25
<------|------|------|------|------|------|------|------|------|------|------|------>
0 25 50 75 100 125 150 175 200 225 250
Number line using multiple of 50
<------|------|------|------|------|------|------|------|------|------|------|------>
0 50 100 150 200 250 300 350 400 450 500
Number line using multiple of 100
<--------|--------|--------|--------|--------|--------|--------|--------|--------|--->
100 200 300 400 500 600 700 800 900
Marking Numbers in the Number Line
- 0
<---------|---------|---------|---------•---------|---------|-------|-------|--->
-3 -2 -1 0 1 2 3 4
- 3
<---------|---------|---------|---------|---------|---------|-------- •-------|----->
-3 -2 -1 0 1 2 3 4
- 5 using number line which is marked with multiples of 2
<------|------|------|--•--|------|------|------|------|------|------|------|------>
0 2 4 ↓ 6 8 10 12 14 16 18 20
5