Length of the tiles is 40 cm.

∴ One part of length =

Width of the tiles = 60 cm

One part of width =

There are two part of length and three parts of width.

Length of shaded portion = 2× 10 = 20 cm

Width of shaded portion = 3× 12 = 36 cm

a) Perimeter of shaded portion = 2(20+36) = 2× 56 = 112 cm

Perimeter of whole design = 2(40+60) = 2× 100 = 200 cm

Ratio of the perimeter of shaded portion to the perimeter of the whole design =

Ratio = 14:25

b) Area of shaded portion = 20× 36 = 720 sq. cm

Area of unshaded portion = area of whole figure – area of shaded portion

= 40× 60 – 720

= 2400 – 720 = 1680 sq. cm

Ratio of the area of the shaded portion to the area of the unshaded portion =

Ratio = 3:7