Area and Perimeter โ GCSE Maths
Introduction

- The amount of space inside of any 2-Dimensional shape is Area.
- Calculation of area for every shape is done in different way.
- The Area is measured in square units.

- The sum of sides of any shape it is made up of is known as Perimeter (the distance around a shape)
- Calculation of Perimeter for almost every shape is common.
- The Perimeter is measured in linear units.
Area and Perimeter of Different Shapes
- Area and Perimeter of Different Shapes:
SQUARE:

- Area: a ร a = (side)ยฒ
- Perimeter: a + a + a + a = 4a (4 ร sides)
RECTANGLE:

- Area: l ร b
- Perimeter: 2 ร (l + b)
CIRCLE:

- Area: ฯ ร radiusยฒ
- Perimeter: 2 ร ฯ ร radius
TRIANGLE:

- Area: (1/2) ร base ร height
- Perimeter: sum of all three sides
TRAPEZIUM:

- Area: (1/2) ร (a + b) ร h
- Perimeter: a + b + c + d
Real life Examples of Area and Perimeter

Solved Example
Problem: Find the area and perimeter of circles with radius equal to:
(i) r = 5cm
(ii) r = 7cm

Solution:ย
(i) The Area and Perimeter of circle with radius 5cm:

(ii) The Area and Perimeter of circle with radius 7cm:

Final Answer: (i) 31.4 cm and (ii) 43.96 cm
Solved Example
Problem: If a rectangular field is of of following dimensions find the its area and length of required fence for the field: Length = 20cm, Breadth = 15cm

Solution:ย
To find the length of required fence for the field we will find out the perimeter:

Final Answer: Area = 300 cm2 and Perimeter = 70 cm
Solved Example
Problem: Find the Area and Perimeter of the following 2 Dimensional shapes

Solution:ย
(a) The Area and Perimeter of Trapezium:

Perimeter of Trapezium:

(b) Area and Perimeter of a square having a side equal to 4cm:

(c) Area and Perimeter of a Triangle with base equal to 4cm and height equal to 4cm:

Final Answer: (a) Area = 36.2 cm2 and Perimeter = 14ย cm, (b) Area = 16 cm2 and Perimeter = 16 cm, (c) Area = 8 cm2 and Perimeter = 12 cm
Solved Example
Problem: Work out the area of the following shapes

Solution:ย
(a) The shape is combination of three shapes the two semi-circles and one square.
The area of this shape will be:

(b)The shape is combination of two Rectangles and one square:

Final Answer: (a) 81.52ย cm2 and (b) 33 cm2