In a quadrilateral ABCD, the angles A, B, C and D are in the ratio 1:2:4:5. Find the measure of each angle of the quadrilateral.
Sum of angles of a quadrilateral ABCD =360∘
Ratio in angles = 1:2:4:5
Let first angle = x
Second angle = 2x
Third angle = 4x
and fourth angle = 5x
∴ x +2x+4x+5x = 360∘
⇒12x=360∘⇒x=360∘12=30∘
∴ First angle=30∘Second angle=30∘×2=60∘Third angle=30∘×4=120∘Fourth angle=30∘×5=150∘