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Question 3:
Length of the fence of a trapezium shaped field ABCD is 120 m. If BC = 48 m, CD = 17 m and AD = 40 m, find the area of this field. Side AB is perpendicular to the parallel sides AD and BC.
Length of the fence of trapezium ABCD = AB + BC + CD + DA
120 m = AB + 48 m + 17 m + 40 m
AB = 120 m − 105 m = 15 m
Area of the field ABCD 
