Considering below equation holds
V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30
Then, I + II + III = ?
60
V + II - VI = 10
=> I = 10
IV - X + VIII = 20
=> II = 20
IV - VII + VI = 30
=> III = 30
I + II + III = 10 + 20 + 30
