Question

A small indoor greenhouse (herbarium) is made entirely of glass panes (including base) held together with tape. It is $30cm$ long, $25cm$ wide, and $25cm$ high.
(i) What is the area of the glass?

Answer 1

Step 1: Given data:

The dimension of the greenhouse is $\left(30cm\times 25cm\times 25\right)$.

The total edges of the greenhouse are $12$,

We know that the surface area of a cuboid is $A=2\left[\left(a\times b\right)+\left(b\times c\right)+\left(c\times a\right)\right]$, where $a,b$ and $c$ are the lengths, width, and height of the cuboid.

Step 2: Finding the area of the glasses:

It is clear that the greenhouse is a cuboid. As we know that the surface area of a cuboid is $A=2\left[\left(a\times b\right)+\left(b\times c\right)+\left(c\times a\right)\right]$

So,

$\begin{array}{rcl}A& =& 2\left[\left(a\times b\right)+\left(b\times c\right)+\left(c\times a\right)\right]\\ & =& 2\left[\left(30\times 25\right)+\left(25\times 25\right)+\left(25\times 30\right)\right]\\ & =& 2\left[750+625+750\right]\\ & \Rightarrow & A=4250c{m}^2\end{array}$

Hence, the area of the glass is $4250c{m}^2$.