Step-by-step explanation:
the total surface area is the sum of the individual areas.
we have the ground area : a 6×6 square. = 36 cm²
and we have 4 equal triangles.
the area of a triangle is baseline × height / 2.
which is for each of these triangles
6 × 12 / 2 = 3 × 12 = 36 cm²
so, the total surface area of the pyramid is
36 + 4×36 = 5×36 = 180 cm²
Answer:
46.67 %
Step-by-step explanation:
Total thickness = 30
14 of this is concrete 14/30 x 100% = 46.67 %
Answer:
Area = 77ft²
Perimeter = 44 9/20 feets
Step-by-step explanation:
Area of a triangle = 1/2 * base * height
Base = 19 1/4 feets = 77/4 feets
Height = 8 feets
Area = 1/2 * 77/4 * 8
Area = (77 * 8) / 8
Area = 77 feet²
Perimeter of a triangle :
Sum of the sides
Perimeter = a + b + c
Perimeter = 19 1/4 + 10 + 15 1/5
Perimeter = 44 + (1/4 + 1/5)
Perimeter = 44 9/20