There is a pentagonal shaped park as shown in the figure. For finding its are Jyoti and Kavita divided it in two different ways.

Find the area of this park using both ways. Can you suggest some other way of finding its area?

In given figure sectors of two concentric circles of radius 7 cm and 3.5 cm are shown. Find the area of the shaded region.

Take a sheet of paper. Measure its area. Pile up such sheets of paper of same size to make cuboid. Measure the height of this pile. Find the volumne of the couboid by finding the product of the area of the sheet and the height of this pile of sheets. This activity illustrates the idea that volume of a solid can ve deduce by thsi method also (if the base and top of the solid are congruent and parallel to each other and its edges are perpendicular to the base). Can you think of such objects whose volumne can be found by using this method?

The perimeter of a circular field is 660cm.A square-shaped portion of the field is demarcated in such a way that its four vertices lie on the outside boundary of the field.Find the area of the square-shaped region of the field.

The shape of the top surface of a table is a trapezium. Find its area if its parallel sides are 1m and 1.2m and perpendicular distance between then is 0.8 m.

The area of a trapezium is 34m^2 and the length of one of the parallel sides is 10 cm and its height is 4 cm. Find the length of the other parallel side.

Find the area of a rhombus whose side is 6cm and whose altitude is 4cm. If one of its diagonals is 8 cm long, find the length of the other diagonal.

Mohan wants to buy a trapezium shaped field. Its side along the river is parallel to and twice the side along the road. If the area of this field is 10500m^2 and the perpendicular distance between the two parallel sides is 100m, find the length of the side along the river.

Rachel,an engineering student,was asked to make a model shaped like a cyclinder with two cones attached at its two ends by using a thin aluminium sheet.The diameter of the model is 3 cm and its length is 12cm.If each cone has a height of 2 cm,find the volume of air contained in the model that Rachel made.(Assume the outer and inner dimensions of the model to be nearly the same).