**Solution:** Every composite number can be expressed (factorised) as a product of primes and this factorisation is unique, apart from the order in which the prime factors occur. Yes.

**Justification:** HCF of two numbers is always a factor of their LCM. But here 18 is a factor of 378.

Hence, Two numbers can have 18 as their HCF and 380 as their LCM.