Area is the amount of space or surface which occupies
a two-dimensional closed plane figure.
A = length × breadth rectangle A = length × length square Area Formulae Two-dimensional geometric figures Names
simple concept about area C B A D The rectangular board is divided with squares of unit size each. We can find the area of any part by counting the number of squares as its unit measure. Thus, Area of A = 2 square units or 2 unit ² Area of B = 3 square units or 3 unit² Area of C = 4 square units or 4 unit² Area of D = 5 square units or 5 unit²
Try out the questions below. Important steps should be shown in the task sheet given. 1)
What is the length of the square above? _____cm
b) What is the perimeter of the square above? _____ cm
c) What is the area of the square above? ______ cm ²
2) 3cm 3cm a) What is the length of the rectangular above? _____cm b) What is the perimeter of the rectangular above? _____cm c) What is the area of the rectangular above? _____cm ²
3) The area of a rectangle is 120cm². If the breadth is 5cm, what is the length? 4) The length of a carpet is 12m. Its breadth is less than the length by 4m. What is the area of the carpet? 5) The area of Ahmad’s school field is 6000m². If the length is 100m, what is the breadth of the field?
space. All things in this world, whether solid, liquid
or gaseous, exist in three dimensions. As such, the
amount of three-dimensional space which an object
occupies is called its volume.
To calculate the volume of an object or solid, we
have to use a specific unit of measure.
The most suitable shape for the unit of volume is a
unit cube with dimensions 1cm × 1cm × 1cm.
A unit cube is a cube whose edges are of unit length. The volume of a unit cube with edges 1cm each is 1cm × 1cm × 1cm = 1cm ³ This unit cube is the unit of measure usually used for measuring volume of a solid. 1cm 1cm 1cm Example: If = 1cm³, find the volume of the solid below. Solution: Volume = 1cm³ × 4 = 4cm³
Volume of cube = length × 3 = l ³ Volume of cuboid = length × breadth × height OR Volume of cuboid = Area of base × height l l l l b h
Try out these questions. Important steps should be shown in the task sheet given.
Siti has a shoe box. Find the volume of the shoe box if its length is 40cm, its breadth is 20cm and its height is 10cm.
2) The volume of a cuboid is 1120cm ³. Its breadth is 8cm. Its height is 7cm. What is its length?
3) The milk container is a cube. What is the length of its side? Milk 1000cm ³ 4) The volume of the pencil case is 720cm ³. What is its length? Pencil case 5cm 8cm
5) The length of the cube is 4cm. The area of the cuboid is 27cm ² What is the total volume of the cube and cuboid? 5cm
What did we learnt here? 2D Shapes 3D Shapes Perimeter Area Volume