# Two cubes, each of side 15 cm are joined end to end. What is the surface area of the resulting cuboid?

Nov 20, 2017

surface area$= 2250 c {m}^{2}$

#### Explanation:

if two cubes of length $15 c m$ are joined, the resulting cuboid will be of dimensions

$30 c m \text{ by " 15cm" by } 15 c m$

see diagram below

surface area will be

each end $= \rightarrow 15 \times 15 = 225 c {m}^{2}$

one top/bottom$= \rightarrow 30 \times 15 = 450 c {m}^{2}$

each side$\rightarrow 30 \times 15 = 450 c {m}^{2}$

total surface area$= 2 \times \left(450 + 450 + 225\right)$

surface area$= 2 \times 1125 = 2250 c {m}^{2}$