Answer:
10
Step-by-step explanation:
Common factors of 110: 1, 2, 5, 10, 11, 22, 55, 110
Common factors of 40: 1, 2, 4, 5, 8, 10, 20, 40.
Common factors of 120: 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60 120.
The common factor of 110, 40, and 120 is 10.