Interior angle : exterior angle = 2 : 1Let interior angle = 2x° & exterior angle = x°
∴ 2x° + x° = 180°
3x = 180°
(i) x = 60°
∴ Each exterior angle = 60°
Let no. of sides = n
∴ 360° /n = 60°
n = 360° /60°
n = 6
(ii)
∴ (i) 60° (ii) 6