Page 232 - ICSE Math 6

11. What happens to the area of a square, if its side is doubled?
12. How many 12 cm long and 5 cm wide tiles will be needed to cover a rectangular region of
measures:
(a) 200 cm by 144 cm (b) 80 cm by 48 cm

AT A GLANCE
¾ Perimeter of a closed figure is the length of its boundary.
¾ Perimeter of a square = 4 × (length of a side)
¾ Perimeter of a rectangle = 2 × (length + breadth)
¾ Perimeter of a triangle = sum of all the sides
¾ Perimeter of an equilateral triangle = 3 × (length of a side)
¾ Area of a closed figure is the surface or region enclosed by its boundary.
¾ Area of a square = (length of a side) 2
¾ Area of a rectangle = length × breadth

MENTAL MATHS

1. Write True or False.
(a) Perimeter of a square = 4 + (length of a side)
(b) Perimeter of a rectangle = 2 × (length × breadth)
(c) Perimeter of an equilateral triangle = 3 × (length of a side)

(d) Area of a square = (length of a side) 2
(e) Area of a rectangle = length + breadth
2. Complete the table.

Length Breadth Perimeter Area
5 cm 6 cm _______ _______

10 m _______ _______ 70 m 2
_______ 4 cm 20 cm _______

3. Find the area of the given figures by counting the squares. 1 cm
1 cm

(a) (b) (c)

(d) (e) (f)

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