Theory:

The closure property of whole numbers states that while operating addition and multiplication with two or more whole numbers, the result of the operation is also a whole number.
While doing the operation of whole numbers if the result of the operation is a whole number, then we can say that it satisfies the closure property.
The result of the addition and multiplication of any two whole numbers is always a whole number.

Consider \(a\) and \(b\) are two whole numbers then:
  • The addition \(a + b\) is a whole number.
  • The multiplication \(a × b\) is also a whole number.
Example:
1 and 9 are two whole numbers then, 1+9=10 is also a whole number.
 
5 and 9 are two whole numbers then, 5×9=45 is also a whole number.
Important!
The result of the subtraction and division is not always a whole number. If \(a\) and \(b\) are two whole numbers, then ab and a÷b is not always a whole number.
Example:
i) 91=8 is a whole number.
 
ii) 19=-8 is a negative number, not a whole number.
 
iii) 105=2 is a whole number.
 
iv) 19=0.111 is a decimal number, not a whole number.
Therefore the closure property of whole numbers states that while operating addition and multiplication with two or more whole numbers, the result of the operation is also a whole number.