Subject: General Aptitude · Chapter: Volume and Surface Area · Exam: · Marks: · Difficulty:
The length of a hall is 20 metres and the width is 16 metres. The sum of the areas of the floor and roof is equal to the sum of the areas of the four walls. Find the volume of the hall.
(a)$2844.4 \mathrm{m}^{3}$
(b)$2866.8 \mathrm{m}^{3}$
(c)$2877.8 \mathrm{m}^{3}$
(d)$2899.8 \mathrm{m}^{3}$
Answer
Answer (as printed): A
Explanation
Let the height of the hall be $h$ metres. Then, $2 \times 20 \times 16=2(20+16) \times h \Rightarrow 72 h=640$ $$\Rightarrow h=\frac{640}{72}=\frac{80}{9} .$$ ∴ Volume of the hall $$=\left(20 \times 16 \times \frac{80}{9}\right) \mathrm{m}^{3}=\left(\frac{25600}{9}\right) \mathrm{m}^{3}=2844.4 \mathrm{m}^{3} .$$