Introduction to number line online

What is number line :

A number line is a straight line on which each and every point is acquired to correspond to a real number (It may be positive and negative).

Every real number is considered to a point. Often we use integers for the number (like 1, 2, 3, 4….) line but it may be decimal (like 1.5, 2.5, and 3.5, 4.4 and so on).

 Here integer type of number line is given bellow:

The range of the number line (integers from -10 to 10), the line includes all real numbers.

Procedure to Draw a "number Line Online "

Process of drawing a number line:

Most of the number lines are represented as horizontal plane.
Zero is the origin of the number line.
Positive numbers (like as: 1, 2, 3, 4,and so on ) lies on the right side of zero (origin point), and similarly negative numbers (like as: -1,-2,-3, -4, and so on) lie on the left side of zero (origin point) of the number line.

An arrowhead in both end of the number line is meant to indicate that the line continues infinite distance in the positive and negative real, which is denoted by R.

Every type of the real number are used in number line
It consists of irrational (like 1.423, 3.14 and so on..) and rational numbers, integers (positive and negative), whole numbers, and the natural numbers (the counting numbers).

Number Line Online : Rules of Drawing Number Line for Inequality

Number line of Inequality:

(i) In the case of the inequality  is "< (less than)" or "> (greater than) " then connect the two points in number line with a "dotted line".  The dotted line is correspondent to the open circle on the number line.

(ii)  In the case of  the inequality is " = (less then equal to)" or "= (greater than equal to) " then connect the two points in the number line with a “Solid line". The dotted line is correspondent to the closed circle  on the number line.

Number Line Online : Example Number Line of Inequality

Basically, number line is design for inequality.

Like as x < 3 and x > -2

It is written as:

-2
In word:          x is greater than -2 but less than 3.

Example of Number Line(word Problem)

Draw the number line in each case :

Ex 1:     (i) A number is greater than -1 but less than 4

Answer:

Let the number be n.

So that, n > -1 and n < 4.

So it can be written as:

-1 < n < 4

Ex 2:

Twice of Age of John is greater than of 40 but less than 80.

Answer:

Let the age of John be x.

So that,

2x > 40

Or, x > 40/2,

Or, x > 20

Again,

2x < 80

Or, x < 80/2

So, N < 40

So that it can be written as:

20

Ex 3:

A number is greater than equal to -2 but less than equal to 3

Answer:

Let the number be N

So that,

N = -2

But, N = 3

So that, it is written as :

-2 = N  =  3

Number Line Online : Range of Number Line

Number line makes to easy determine which numbers are bigger or smaller.

Let an example:

-5
Determine the range of X.

Solve:

3 is the bigger than -5.

We know that,

Range = Bigger value – lower value

Range = 3 – (-5)

Range = 3 + 5 = 8 units

Practice Problems on Number Line Online

Draw number line and explain in each case:

1)      A number less than 6 but greater than -3.

 2)      Cost of a pen is greater than   dollar 2 but less than dollar 8.

 3)      Income of a Mr. John is varies from   dollar 800 to dollar 1000

 4)       Temperature of California   varies from 4 °C to 14 °C.