Find the prime factorization of 25
25 = 5 × 5
Find the prime factorization of 120
120 = 2 × 2 × 2 × 3 × 5
Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:
LCM = 2 × 2 × 2 × 3 × 5 × 5
LCM = 600