HCF and LCM of Numbers

"HCF and LCM of Numbers "
  
Let's start with the definition of the two terms HCF (also called as GCD) & LCM.

■ HCF
  •It stands for Highest Common Factor.
  • It is defined as the greatest number  
  which is a common factor of two or more    given numbers.
    • It is also called as Greatest Common Divisor(GCD)  or Greatest Common Measure (GCM).
 
For example  35,45
   35 = 5×7
   45=5×3×3
From the above we notice that the Greatest Common Factor is 5.

■ LCM
•It stands for Least Common Multiple
•It is defined as the smallest number which is a multiple of each other.

   For eg:- 3,6
        LCM (3,6)=6

Now  let's look into one more small concept
Co- prime Numbers which is useful here.

Two Numbers are said to be Co-prime  or relative prime , if their HCF is "One" .

   There are many such numbers.
Example:-HCF of 11,13 is 1

Therefore , 11 & 13 are co prime numbers.