Question

The length of a cuboid having breadth $=4cm$, height $=4cm$ and total surface area $=148{cm}^2$ is

Answer 1

Given: Breadth of the cuboid, $b=4cm$
Height of the cuboid, $h=4cm$
Let the length of the cuboid be $lcm$
As, total surface area of the cuboid $=148{cm}^2$
$\Rightarrow 2(lb+bh+hl)=148$
$\Rightarrow 2\left[l\right(4)+(4\left)\right(4)+(4\left)l\right]=148$
$\Rightarrow \left[l\right(4)+16+(4\left)l\right]=74$
$\Rightarrow 4l+4l=74–16$
$\Rightarrow 8l=58$
$\Rightarrow l=7.25cm$
Thus, the length of cuboid is $7.25cm$.