Avneet buys 9 square paving slabs, each with a side 12 m. He lays them in the form of a square.
(a) What is the perimeter of his arrangement?
(b) Shari does not like his arrangement. She gets him to lay them out like a cross. What is the perimeter of her arrangement?
(c) Which has greater perimeter?
(d) Avneet wonders, if there is a way of getting an even greater perimeter. Can you find a way of doing this? (The paving slabs must meet along complete edges, i.e., they cannot be broken.)
(a) Perimeter of the square = 4× side.
Length of the side of the square =3 square slabs × length of each side
=3×0.5m=1.5m [∵each side=12 m]
Perimeter of Avneet's arrangement =4×1.5 m=6 m
(b) Consider the figure
Perimeter of the figure =5× length of each side =5×0.5 m=2.5 m [∵each side=12 m]
Perimeter of the cross =4× figure =4×2.5 m=10 m
(c) Shari's arrangement (cross) has greater perimeter.
(d) No, but we can achieve the same perimeter as Shari's arrangement by arranging all the squares in a row.