### Mensuration - Revision Notes

CBSE Class 8 Mathematics

Revision Notes

Chapter – 11

Mensuration

Revision Notes

Chapter – 11

Mensuration

- Perimeter: Length of boundary of a simple closed figure.

Perimeter of:

Rectangle = 2(l + b)

Square = 4a

Parallelogram = 2(sum of two adjacent sides) - Area: The measure of region enclosed in a simple closed figure.
- Area of a trapezium = half of the sum of the lengths of parallel sides × perpendicular distance between them.
- Area of a rhombus = half the product of its diagonals.
- Triangle = x base x height
- Diagonal of:

Rectangle =

Square = - Surface area of a solid is the sum of the areas of its faces.
- Surface area of:

a cuboid = 2(lb + bh + hl)

a cube = 6l2

a cylinder = (r + h) - Amount of region occupied by a solid is called its volume.
- Volume of

a cuboid = l x b x h

a cube = l3

a cylinder = r2h - (i) 1 cm3 = 1 ml
- (ii) 1L = 1000 cm3
- (iii) 1 m3 = 1000000 cm3 = 1000L