72 ... I think
The lowest common denominator is 30
The lowest common denominator is 10
20 is the lowest common denominator for 4 and 10.
9/10 is already in its lowest term.
The lowest common denominator would be 10, so 1/2 would be 5/10 and 1/5 would be 2/10.
110
10 is.
100
60
360
LCD(10, 8, 7) = 280.
10