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 of tape is needed for all the 12 edges?
(i) Length (l) of green house = 30 cm
Breadth (b) of green house = 25 cm
Height (h) of green house = 25 cm
Total surface area of green house
= 2[lb + lh + bh]
= [2(30 × 25 + 30 × 25 + 25 × 25)] cm2
= [2(750 + 750 + 625)] cm2
= (2 × 2125) cm2
= 4250 cm2
Therefore, the area of glass is 4250 cm2
(ii) It can be observed that tape is required alongside AB, BC, CD, DA, EF, FG, GH, HE, AH, BE, DG, and CF
Total length of tape = 4(l + b + h)
= [4(30 + 25 + 25)] cm
= 320 cm
Therefore, 320 cm tape is required for all the 12 edges