Question

The area of $4$walls of a cuboid is $448{cm}^2$, its length is $18cm$ and height is $8cm$. What is its breadth (in $cm$)?

Answer 1

Step 1: Use the formula of area of four wall

Let $b,h$ and $l$ be breadth, height, and length respectively.

Given length $\left(l\right)=18cm$

height $\left(h\right)=8cm$

Area of four walls of cuboid $=448{cm}^2$

Area of four walls of cuboid $=2\times h(b+l)$

$\Rightarrow 2h(b+l)=448$

$\Rightarrow 2\times 8\left(b+18\right)=448$

Step 2: Solve the above equation

$\Rightarrow (b+18)=\frac{448}{16}$

$\Rightarrow b+18=28$

$\Rightarrow b=28-18$

$\Rightarrow b=10cm$

Hence, the breadth of the cuboid is $10cm$