Given angles are x°, (x + 10)°, (x + 20)°, (x + 30)°
Sum of the four angles = x + x + 10° + x + 20° + x + 30° = 4x + 60°
But the sum of the four angles = 360°
4 x 60° = 60° = 360°
4x = 360° – 60° = 300°
x = 300∘/4 = 75°
∴ The angles are x = 750
x + 10°- 75°+ 10° = 85°
x + 20° = 75° +20° = 95°
x + 30° = 75° + 30° = 105°
