HCF of QQQ 3-digit number and 481

A 3-digit number of the form QQQ can be mathematically expressed as Q × 111. The prime factorization of 111 is 3 × 37. Therefore, P = Q × 3 × 37. Now, find the prime factorization of 481. Testing primes up to √(481) ≈ 21, we find it is divisible by 13: 481 = 13 × 37. Both numbers explicitly share the prime factor 37. Since Q is a single non-zero digit (1 \le Q \le 9), Q cannot contain the factor 13. Thus, the Highest Common Factor between P and 481 is exactly 37.

Answer: (c).