Question

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

Answer 1

When three cubes are joined side by side, the resulting cuboid has the same width (breadth), $b=5cm$ and height, $h=5cm.$ but length, $l=5+5+5=15cm.$

Surface Area of the resulting cuboid $=2(lb+bh+lh)$

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

$=2(75+25+75)=2\times 175=350c{m}^2.$