Find the surface area of the pyramid with square base that measures 8 ft by 8 ft and slant height of 12 ft.

Slant surface is composed of 4 triangles each of 8' base B and height H of 12'.
Area of each triangle is therefore 
A=(1/2)BH
=(1/2)(8)(12)
=48 sq. ft
Total slant surface area = 4A = 192 sq. ft.

Area of square base = 8*8 = 64 sq. ft

Total surface area = 192+64 = 256 sq. ft.

40%=2/550=1/230=3/1056=14/25