Question

A small indoor greenhouse (herbarium) is made entirely of glass panes (including base) held together with tape. It is 30 cm long, 25 cm wide and 25 cm high.
(I) what is the area of the glass?
(ii) How much tape is needed for all the 12 edges?

Answer 1

Hint: Here we go through by applying the formula of total surface area of a cuboid to find out the area of the glass that is used to make the greenhouse. And for finding the length of the tape we have to just find the total lengths of the edges.

Complete step-by-step answer:

Here in the question it is given that a small indoor greenhouse whose dimensions are given as 30 cm long, 25 cm wide and 25 cm high.
It means that l=30cm, b=25cm and h=25cm.
And we know that the formula of total surface of a cuboid is $2(lb + bh + hl)$
By putting the values in the formula we get,
Total surface area of greenhouse=$2(30 \times 25 + 25 \times 25 + 25 \times 30) = 4250c{m^2}$
Hence for question (I) the total surface area of the glass is $4250c{m^2}$
And for the (ii) question we have to find out the lengths of the edges where the tape should be applied.
And we all know that the cuboid has 12 edges in which 4 edges are length, 4 edges are breadth and the rest 4 edges are height.
Therefore for the total length of the edges we can write it as= 4l+4b+4h.
And by putting the value we get,
=4(30+25+25) =320cm
Hence for question (ii) the length of tape is needed for all the 12 edges is 320cm.

Note:Whenever we face such a type of question the key concept for solving the question is to just read the question carefully and think about the formula that are used for finding the result here in this question it is asking for the total surface area so we simply put the formula of total surface area for finding our result.