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\ 06-Jan-2025 Bharat Arora Proof-7 Reader’s Sign _______________________ Date __________

1. ................ is the part of a plane occupied by a closed figure.
(a) Area (b) Perimeter (c) Circumference (d) Length

2. A wire is bent to form a square of side 11 cm. If the wire is again rebent to form a circle, its
radius will be
(a) 22 cm (b) 11 cm (c) 5.5 cm (d) 7 cm

3. The area of a rectangle and the area of a circle are equal. If the dimensions of the rectangle
are 14 cm × 11 cm, then the radius of the circle is
(a) 21 cm (b) 10.5 cm (c) 14 cm (d) 7 cm
1
4. Area of a ................ = × base × height
2
(a) square (b) rectangle (c) parallelogram (d) triangle
5. The perimeter of a semicircle with radius r cm is

(a) 2pr cm (b) pr cm (c) r(p + 2) cm (d) r(p + 1) cm
6. A rectangular piece of dimensions 3 cm × 2 cm was cut from a rectangular 6 cm
sheet of paper of dimensions 6 cm × 5 cm. The area of remaining sheet of
paper is 5 cm 3 cm
(a) 22 cm 2 (b) 24 cm 2 2 cm
(c) 30 cm 2 (d) 36 cm 2

Area of Simple Geometric Shapes

Father: Son! Before finding the area of an irregular polygon-shaped figure, first tell me what you
have learnt about the perimeter and area of geometric figures so far.
Raman: Papa! Perimeter is the distance around the boundary of a closed plane figure, and the
area is the region covered by it.

I can find the perimeter and area of various plane figures such as triangles, rectangles, circles,
etc. and can also apply them in real-life applications such as finding the area of the pathways of
a park or garden and the area of four walls of a room, etc.
Look at the following chart for finding the perimeter and area of geometrical figures.

Shape Rectangle Square Triangle Parallelogram Circle

l a
Diagram b b a a c h a h l O r
l a b
b
Perimeter (P) 2 × (l + b) units 4 × a units (a + b + c) units 2 × (l + b) units 2pr units
2
Area (A) l × b sq. units a × a or 1 × base × height b × h sq. units pr sq. units
2
a sq. units 2
1
Or × b × h sq. units
2

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