The HCF of two numbers is $13$ and their LCM is $4095$. If one of the numbers is $819$, find the other numbers

Question

Stuck on this question. My Workings:

$$4095 = 3^2 * 5 * 7 * 13$$ $$819 = 3^2 *7 * 13$$

and I'm lost after this part. Help would be appreciated. Thank You

Answer 1

Hint: the product of gcd and lcm of two numbers $a,b$ equals $ab$. So the product is $$ ab=13\cdot 4095. $$ Now $a=819$. Can you finish?

Answer 2

Hint:

If the numbers are $a$, $b$ then:

$$\text{HCF}(a,b)*\text{LCM}(a,b)=a*b$$