Sum of four angles of quadrilateral = 360° Ratio between three angles = 3x, 5x, 9x Fourth angle = 71° 360° − 71° = 289° Sum of three angles = 289° 3x + 5x + 9x= 289° 17x = 289° x =
289°
17
= 17° Angles ⇒ 3x = 3 × 17 = 51° 5x = 5 ×17 = 85° 9x = 9 ×17 = 153° Difference between the largest and the smallest 153° − 51° = 102°