The angles of a quadrilateral are in the ratio 2:4:5:7. Find the angles.

Our given ratio of angles is 2:4:5:7. Let common multiplying factor be x°.


Hence, A = 2x°, B = 4x°, C = 5x° and D = 7x°
Since the sum of the angles of a quadrilateral is 360°, we have:
2x + 4x + 5x + 7x = 360°


18 x = 360°
x = 20°
A = 40°; B = 80°; C = 100°; D = 140°


Hence, the measure of the angles are 40°, 80°, 100° and 140°


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