Concept:The area of a trapezium depends on the average length of its parallel sides multiplied by the perpendicular height.Explanation:Let the parallel sides be a and b.Use the trapezium area formula:Area=21(a+b)hGiven: Area =200cm2 and height h=16cm.Substitute the values:21(a+b)×16=200Simplify:8(a+b)=200a+b=25— (1)The sides are in the ratio 2:3, so let a=2x and b=3x.Then from (1):2x+3x=255x=25x=5Therefore:a=2×5=10cmb=3×5=15cmThe lengths of the parallel sides are 10cm and 15cm.