Question

There are five odd numbers $1,3,5,7,9$. What is the HCF of these odd numbers?

• A. $2$
• B. $1$
• C. $6$
• D. $5$

Answer 1

The correct option is B $1$

Let us calculate and check what is the highest common factor for these numbers.

First finding the factors of individual numbers:

Factors of $1=1$

Factors of$3=1,3$

Factors of $5=1,5$

Factors of $7=1,7$

Factors of $9=1,3,9$

HCF is $1$ for the five odd numbers.

Therefore, $B$ is the correct answer.