Question

if a and b are relatively prime no then what is their hcf

Answer 1

HCF of any two relative prime number is 1

Example:
2 and 3 two relative prime number.

HCF of 2 and 3:

2 = 2 × 1
3 = 3 × 1

HCF is 1.

Answer 2

If a and b are relatively prime no then , their HCF is 1 .
Because , HCF means highest common factor . no two prime numbers will have common factor greater than 1.
CHECK IT ONCE:
For eg , take two prime numbers  23 and 2,
             they have one and only common factor , that is 1. It has no other common factor. Then we no need to bother about the highest one. since there is only one common factor 1