Page 13 - E-Book prim 4

Delta Modern Language Schools

Primary stage
Maths Department

Prim 4 2024-2025

Unit (4) : Area and perimeter

Calculating perimeter:

Perimeter is the distance around the figure

EX: Perimeter of triangle = 5 + 5 + 6 =16 cm

Calculating perimeter of square :

Square

All side lengths of square are equal

( S: side length )

Perimeter of square = S + S + S + S
= S X 4
Side length (s) of square = perimeter of square ÷ 4

Area of square = Side length x itself
= S x S

Rectangle

each two opposite side are equal

(L : Length , w : width)

Perimeter of rectangle = L + W + L + W

= 2L + 2W
= ( L + W ) X 2

Half of perimeter = length + width

Area of rectangle = length x width

Width of rectangle = Area ÷ length

Length of rectangle = Area ÷ width

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