Question

Ramona is painting the entire surface of a block of wood in the shape of a right rectangular prism. The block of wood has a length of 8 in., a width of 3 in., and a height of 5 in. What is the total area she will paint?

Answer 1

Surface Area of the top and bottom =
2•8•3 = 48 in²

Surface Area of the lateral side rectangle =
(8+8+3+3) • 5 = 110 in²

Total Surface Area = 48+110 = 158 in²

Answer: 158 in²

Answer 2

158 in²

Explanation:

Data:

l = 8 in

w = 3 in

h = 5 in

Calculations:

Front + Back = 2 × (8 in × 5 in) = 2 × 40 in² = 80 in²

Top +Bottom = 2 × (8 in × 3 in) = 2 × 24 in² = 48 in²

Two ends = 2 × (5 in × 3 in) = 2 × 15 in² = 30 in²

Area = 158 in²

Ramona will paint 158 in² of surface.