Since it’s asking for square inches on a rectangular prism, this is solving for surface area. So we use the following formula:
2(h*w)+2(h*l)+2(w*l)=A
2(10*8)+2(10*12)+2(8*12)
2(80)+2(120)+2(96)
160+240+192
592
592 sq. in.
Answer:
Water needed for pool = 486 cubic feet
Plastic liner required for the pool = 298.3 feet
Step-by-step explanation:
Top view of the pool is a composite figure, having one rectangle and a trapezoid.
1). Water needed for the pool = volume of the pool
Volume of the pool = Area of the base × Depth
= (Area of the rectangle + Area of the trapezoid)× depth
Area of the trapezoid = 
= 
= 105 ft²
Area of the rectangle = Length × width
= 11 × 1.5
= 16.5 ft²
Now, volume of the pool = (105 + 16.5) × 4
= 121.5 × 4
= 486 cubic feet
b). Liner required = surface area of the pool excluding top
= Surface area of the walls + Area of the pool base
= (Perimeter of the pool) × depth + area of the base
= (12 + 11 + 1.5 + 10.7 + 9)×4 + 121.5
= 176.8 + 121.5
= 298.3 square feet
Therefore, amount of water required = 486 cubic feet
liner needed = 298.3 square feet