Presentation is loading. Please wait.

#  Counting numbers are called natural numbers.  It is denoted by N. N=(1,2,3,4………………)

## Presentation on theme: " Counting numbers are called natural numbers.  It is denoted by N. N=(1,2,3,4………………)"— Presentation transcript:

 Counting numbers are called natural numbers.  It is denoted by N. N=(1,2,3,4………………)

 Natural numbers together with 0 are called whole numbers. It is denoted by W. W=(0,1,2,3,4……………..)

 The numbers less than 0 are called negative numbers. -1,-2,-3,-4……….

 The collection of whole numbers and negative numbers are called integers. It is denoted by I or Z.  I or Z=(………. -3,-2,-1,0,1,2,3,4……….)

 The numbers which can be written in the form of p/q, where q≠0 and p,q are integers are called rational numbers. It is denoted by Q. for example:- -1/2,-5/7, 2/3,0/1 etc.

 Closure property

 So rational numbers are closed under addition.  If a and b are any two rational numbers, then a+b is also a rational number.

 So rational numbers are closed under subtraction.  If a and b are any two rational numbers, then a-b is also a rational number.

So rational numbers are closed under multiplication. If a and b are any two rational numbers, then axb is also a rational number.

 7÷0=not defined  So for any rational number a, a÷0 is not defined.  So rational numbers are not closed under division.  If a and b are any two rational numbers, then a÷b is not a rational number.

Download ppt " Counting numbers are called natural numbers.  It is denoted by N. N=(1,2,3,4………………)"

Similar presentations

Ads by Google