National Curriculum Standard: “Students use formulas for the area and perimeter of rectangles.”
The perimeter of a rectangle is calculated by adding the four sides. The area of a rectangle is calculated by multiplying the length by the width.
Perimeter =2 x (L+W) = 2L + 2W
Area = Length x Width = LW
Find at least three rectangles around the classroom and measure the length and width. Draw a sketch showing the object and the measurements, including the units (millimetres, centimetres or metres). Calculate the perimeter and the area of the object using the formulae above.
For example; your laptop, the table top, your maths book, a window pane, the door, the whiteboard, the front of the heater, the noticeboard etc.
The perimeter of the locker door will be:
(2 x 35) + (2 x 59) = 70 + 118 = 188 cm
The area of the locker door will be:
35 x 59 = 2065 cm^2 (square centimetres)