2021 · Q14
The LCM of two prime numbers p and q is 2231, where p > q. What is the value of p − q ?
Elementary MathematicsHCF and LCM
- A67
- B70
- C74
- D81
Explanation
The LCM of two distinct primes is their product, so pq = 2231. Factoring, 2231 = 23 × 97 (check: 23 × 97 = 2231). With p > q, p = 97 and q = 23, so p − q = 74. This is option (c).