(3) Let the first angle = 3x°; the second angle = 5x°; third angle = 9x° The total sum of all the angles of a quadrilateral is 360°. Now, 3 x + 5 x + 9 x + 71 = 360 x = 17 Therefore, First angle = 3 × 17 = 51° Second angle = 5 × 17 = 85° Third angle = 9 × 17 = 153° Fourth angle = 71° The difference between the largest and smallest angles = 153° - 51° = 102°