If 13 and 518 are both denominators, the LCD is 6734 If that's 1/3 and 5/18, the LCD is 18 and you can change 1/3 to 6/18
The LCD of 1/3 and 1/8 is 24.
lcd of 18 and 16 = 144
LCD(20, 6) = 60
LCD(18, 21) = 126
LCD(5, 18) = 90
18 is.
18
LCD(7,9,13) = 7*9*13 which is 819
LCD(13, 16) = 208
the LCD is 6
lcd(9, 6) = 18.