Factor them.
3 x 5 x 5 = 75
3 x 3 x 3 x 7 = 189
Combine the factors, eliminating duplicates.
3 x 3 x 3 x 5 x 5 x 7 = 4725, the LCM
The LCM is: 4,725
The LCM is: 4,725
The LCM is: 189
lcm 42 and 189
The LCM is: 189
4725.189 = 3*63 = 3*3*21 = 3*3*3*7.75 = 3*25 = 3*5*5.The LCM needs 3 3's, 2 5's and a 7. ... (Leave out the 3 from 75 since there are already 3's in 189.)LCM = 3*3*3*5*5*7 = 27*25*7 = 675*7 = 4725.
The LCM is 189.
The Least Common Multiple of 189 and 42 is 378.
The LCM is 189.
The LCM is 189.
lcm: 189
The LCM is: 83,538