P4 Area and Perimeter

Area & Perimeter Primary 4 Mathematics

Chapter Learning Outcomes
Area and perimeter for rectangles and squares
Area and perimeter for composite figures

Rectangles and Squares: Perimeter and Area This is a rectangle. We can label the sides as its length and breadth.

Rectangles and Squares: Perimeter and Area This is a square. We can label the sides as its length and breadth; all 4 sides are equal.

Rectangles and Squares: Perimeter and Area The perimeter of a rectangle or square is the sum of all of its 4 sides.

Rectangles and Squares: Perimeter and Area Perimeter of rectangle = Length + Length + Breadth + Breadth Perimeter of square = 4 x Length

Rectangles and Squares: Perimeter and Area The area of a rectangle or square is the product of its length and breadth.

Rectangles and Squares: Perimeter and Area Area of rectangle or square = Length x Breadth

Example
Benji bent a length of wire around a rectangular photo frame. How long was the length of wire?
Length of wire = Perimeter of frame = 16 cm + 16 cm + 9 cm + 9 cm = 50 cm The wire was 50 cm long.

Example
Cherie cut out a square piece of cloth with length 12 cm. What was the area of the piece of cloth?
Area of square = 4 x Length = 4 x 12 cm = 48 cm 2 The piece of cloth had an area of 48 cm 2 .

Composite Figures: Perimeter and Area This composite figure can be broken down into a square and a rectangle. I can break it down into two rectangles.

Example
Find the perimeter of the figure ABCDEF.
BC = AF – DE = 5 cm CD = FE – AB = 7 cm Perimeter = 5 cm + 7 cm + 25 cm + 22 cm + 32 cm + 17 cm = 108 cm

Example
Find the area of the figure ABCDEF.
BC = AF – DE = 5 cm CD = FE – AB = 7 cm Area = (25 cm x 5 cm) + (32 cm x 17 cm) = 125 cm 2 + 544 cm 2 = 669 cm 2

Example
Craig is laying turf grass in his garden. What is the perimeter and area of the garden covered by turf grass?
Perimeter = 23 m + 13 m + 6 m + 6 m + 11 m + 6 m + 6 m + 13 m = 84 m

Example
Craig is laying turf grass in his garden. What is the perimeter and area of the garden covered by turf grass?
13 m – 6 m = 7 m Area = (23 m x 6 m) + (6 m x 6 m) + (6 m x 6 m) = 138 m 2 + 36 m 2 + 36 m 2 = 210 m 2

Reference - Textbooks Learning Outcomes Rectangles and squares 4B Pg 98 – 104 4B Pg 100 – 104 Composite figures 4B Pg 105 – 116 4B Pg 105 – 111

P4 Area and Perimeter

by pangwanching on Aug 20, 2010

Accessibility

Categories

Upload Details

Usage Rights

2 Embeds 56

Statistics

P4 Area and Perimeter — Presentation Transcript

http://edp4b2010.blogspot.com	53
http://buzzythings.blogspot.com	3