Answer for LCD is 300
Explanation - looking for LCD (lowest common denominator).
300 is the lowest number divisible by:
25 x 12
30 x 10
4 x 75
Using Prime factorization
25 = 5 x 5
30 = 3 x 2 x 5
4 = 2 x 2
Multiply these factors together
5 x 5 x 3 x 2 x 2 = 300
300 is your LCD