Page 13 - 2024 prim 4 SUMMERY_Neat
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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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