Question

For positive $x$ and $y$, the LCM is $225$ and HCF is $15$. There

• A. Is exactly one such pair
• B. Are exactly two such pairs
• C. Are exactly three such pairs
• D. Are exactly four such pairs

Answer 1

The correct option is B Are exactly two such pairs

Given : LCM $=225$ and HCF $=15$

Let $x=\frac{LCM}{HCF}=15$.

So, $x$ can be written as product of $3,5$ and also the product of $1,15$ which are relatively prime.

Thus, there exist two such pairs where LCM $=225$ and HCF $=15$.

Hence, option B is correct.