The ratio of two numbers is $3:4$ and HCF is $4$ then find the LCM of the two numbers.

Given, the ratio of two numbers is $3:4$.

Let the numbers are $3x$ and $4x$.

Then HCF of the two numbers is $x$.

According to the problem $x=4$.

Then the numbers are $12,16$.

Now LCM of the numbers are $48$.