Certain Operations on Whole Numbers:
(i) Odd ± Odd = Even
(ii) Even ± Even = Even
(iii) Odd ± Even = Odd
(iv) Even ± Even ± Even ........... n terms = Even
(v) Odd ± Odd ± Odd .............. n terms = Even if n is Even, Odd if n is Odd
(vi) Odd × Odd = Odd
(vii) Even × Odd = Even
(viii) Even × Even = Even
(ix) Even × Even × Even ....... n terms = Even
(x) Odd × Odd × Odd ....... n terms = Odd
(xi) (Even)^{n} = Even
(xii) (odd)^{n} = Odd
(a) Prime Numbers: Being Prime is a property of Natural Numbers. All those numbers which are divisible by exactly 2 numbers, i.e. itself and unity "1".
Example: 2, 3, 5, 7, 11 etc.
(b) Composite are the numbers which are divisible by more than 2 numbers, i.e. itself, unity "1" and at least one other.
Example: 4, 6, 8, 9, 10 etc.
1 is neither Prime nor Composite.
All Prime numbers are Odd
Sum of Any 2 prime numbers is always Even
Product of Any two prime numbers is always Odd
There are no 4 digit Prime numbers.
➢ Property of Prime Numbers
207 videos156 docs192 tests

1. What is the number system? 
2. What are the different types of numbers in the number system? 
3. What are the properties of numbers in the number system? 
4. How is the number system used in everyday life? 
5. How does the number system relate to other branches of mathematics? 
207 videos156 docs192 tests


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