Question

What will be the HCF of two consecutive odd numbers?

Answer 1

Highest common factor (HCF).

The highest common factor (HCF) of two or more numbers is the largest number that divides each of the given numbers without leaving any remainder.

Two consecutive odd numbers will not contain any common factors except $1$. So, their HCF will be $1$.

Example.

Let us consider that two consecutive odd numbers are $13$ and $15$.

Factors of $13$ are $1,13$

Factors of $15$ are $1,3,5,15$

The highest common factor from $13\mathrm{and}15$ is $1$.

Hence, the HCF of two consecutive odd numbers is $1$.