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Question
There are two cuboidal boxes as shown in the adjoining figure. Which box requires the lesser amount of material to make?
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| (a) | (b) |
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Solution
For this we find their areas -
(a) Length of the first box (l) = 60 cm
Width of first box (b) = 40 cm
Height of first box (h) = 50 cm
Total surface area of first box = 2(lb + bh + hl)
= 2(60 × 40 + 40 × 50 + 50 × 60)
= 2(2400 + 2000 + 3000)
= 2 × 7400
= 14800 cm2
(b) Length of the second box (l) = 50 cm
Width of second box (D) = 50 cm
Height of second box (h) = 50 cm
Total surface area of second box = 2(lb + bh + hl)
= 2(50 × 50 + 50 × 50 + 50 × 50)
= 2(2500 + 2500 + 2500)
= 2 × 7500
= 15000 cm2
Here the area of the first box is less. Hence, less material is required to make it.
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