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4. A rectangle of sides 12 cm and 8 cm cut into two triangles diagonally. Find the area of each triangle.

5. A square of side 5 cm divides into 2 triangles through a diagonal. Find the area of each triangle.
2
6. The area of a rectangular sheet is 500 cm . If the length of the sheet is 25 cm, what is its width? Also
find the perimeter of the rectangular sheet.
2
7. Find the breadth of a rectangular plot of land, if its area is 440 m and the length is 22 m. Also, find
its perimeter.
8. The perimeter of a rectangular sheet is 100 cm. If the length is 35 cm, find its breadth. Also find the
area.
9. A wire is in the shape of a square of side 10 cm. If the wire is rebent into a rectangle of length 12
cm, find its breadth. Which encloses more area, the square or the rectangle?
10. The area of a square and a rectangle are equal. If the side of the square is 40 cm and the breadth of
the rectangle is 25 cm, find the length of the rectangle. Also, find the perimeter of the rectangle.
11. Two plots of land have the same perimeter. One is a square of side 36 cm and another one is rectangle
whose length is 30 cm. Which plot has the greater area and how much?
12. A door of breadth 1.1 m and height 2 m is fitted in a wall. The length of a wall is 4.5 m and the height
2
is 3.6 m. Find the cost of white washing the wall at the rate of `20 per m .
13. The shaded portion in the following diagram shows two paths inside a rectangular garden. Find the
area of two paths.
40 m

2 m
30 m

2 m
14. A path 8 m wide runs along inside a square park of side 120 m. Find the area of the path. Also find
the cost of cementing it at the rate of `175 per 10 m .
2
15. A 3 m wide path runs outside and around a rectangular park of length 125 m and breadth 65 m. Find
the area of the path.

Area of a Parallelogram

Sameer: I have recalled the concept of perimeter and area of rectangle and square. But, how can
I find the area of this parallelogram shaped wooden frame?
Carpenter: I will teach you.

As you know that a parallelogram is a special type of quadrilateral
having a pair of opposite sides parallel. Also, its opposite sides
are of equal length and opposite angles are of equal measures.
The area of a parallelogram is the region bounded by the
parallelogram.

To find the area of a parallelogram, convert it into a rectangle.
Let us perform an activity.

287 Perimeter and Area