Question

Mohan wants to buy a trapezium shaped field. Its side along the river is parallel to and twice the side along the road. It the area of this field is 10500 m2 and the perpendicular distance between the two parallel sides is 100 m, find the length of the side along the river.

Answer 1

Let the length of the field along the road be l m. Hence, the length of the field along the river will be 2l m. 
Area of trapezium = \(\frac{1}{2}\) (Sum of parallel sides) (Distance between the parallel sides)
\(10500 =\)\(\frac{1}{2}\) \((2l + l) × 100\)
\(2 × 10500 = 3l × 100\)
\(21000 = 300l\)
\(l = 70 m\)

Thus, length of the field along the river \(= (2 × 70) m = 140 m\).