UPSC CDS 2 2020 Math Paper

As we know sum of all interior angles = (n−2)×180°
And sum of all exterior angles = 360°
Now the given condition ⇒(n−2)×180°=2×360°
Now the given condition ⇒ (n−2)×180°=2×360°
n−2=4
n=6
hence the polygon is Hexagon.