Each side of the triangle = a

Perimeter of the triangle = 3a

∴ s = 3a / 2

Hence, area of the signal board = **a**^{2} / 4 \3 sq units Ans.

Now, perimeter = 180 cm

Each side of the triangle = 180/ 3 cm = 60 cm

Area of the triangle = ( 60)^{2} / 4 × 3 cm^{2} =** 900\ 3 cm**^{2} Ans.