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Can we say all natural numbers are whole numbers?___________

                       •Is the vice versa true even?_____________


                       Can we say all whole numbers are natural numbers? _________.

                       •Is the vice versa true even?_______


                       Can we say all integers are rational numbers? _________.

                       •Is the vice versa true even?_______


                       Give five examples of rational numbers. And write respective values of p and q.



                 Properties of rational numbers:


               1) Closure Property: For two rational numbers say a and b the results of addition,
               subtraction and multiplication operations give a rational number. We can say that
               rational numbers are closed under addition, subtraction and multiplication. For example:


                     (2/5)+(1/3) = 11/15
                     (4/6) – (1/3) = 2/6= 1/3
                     (7/3). (5/2) = 35/6
                  The division is not under closure property because division by zero is not defined.


               2) Commutative Property:
               For rational numbers, addition and multiplication are commutative.

               Commutative law of addition: a+b = b+a

               Commutative law of multiplication: a×b = b×a.
                                        3
                             3
                                                                3
                                                            3
                    Eg:    2  × =  6  ; → ×  2  =  6  ; →  2  × = ×  2
                         11  5   55     5   11   55    11   5   5   11


                           3         −5
                  Take a=          =   , check if rational numbers follow commutative property under
                           4          3
                  subtraction and division.
               3) Associative Property:
               Rational numbers follow the associative property for addition and multiplication.

               Suppose a, b and c are rational then
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