Question

Three cubes each of side $5cm$ are joined end to end. What is the surface area of the resulting cuboid?

• A. $300{cm}^2$
• B. $350{cm}^2$
• C. $375{cm}^2$
• D. $400{cm}^2$

Answer 1

The correct option is B $350{cm}^2$

Length of each side of cube $=5cm$

Now, $3$ cubes are joined end to end.

So, the length of the resulting cuboid will be $\left(l\right)=5+5+5=15cm$

But, the breadth and height will remain the same.

So, Breadth $\left(b\right)=5cm$ and Height $\left(h\right)=5cm$

Surface area of the cuboid $=2(lb+bh+hl)$

$=2(15\times 5+5\times 5+5\times 15)$

$=2(75+25+75)$

$=2\times 175$

$\therefore$ Surface area of the cuboid $=350c{m}^2$