A common denominator, though not the least one, is 180.
LCD(3, 12, 15) = 60
The common denominator of any two or more whole numbers will always be 1.
420
The common denominator of any two or more whole numbers will always be 1.
LCD(15, 12, 4) = 60.
60
120
60 I think
The common denominator of 15 and 9 is 45.
The Greatest Common Denominator is 12
12 and 15 go into the denominator 60. 1 and 3 go into 12 and 15.
A common denominator is 84.