Question

A hall is $15$ m long and $12$ m broad. If the sum of the area of the floor and the ceiling is equal to the sum of the areas of the four walls the volume of the hall is

• A. $720m^3$
• B. $900m^3$
• C. $1200m^3$
• D. $1800m^3$

Answer 1

Answer: (C)

$1200m^3$

Given that length $=15$ m and breadth $=12$ m

And area of four walls $=$ area of floor $+$ area ceiling

Let the height is $h$ m

Then area of four walls $=2(15+12)h$ sq.m

And area of calling and floor $=$ $2(15\times 12)$ sq.m

So, $2(15+12)h=2(15\times 12)$

$\Rightarrow 27h=180$

$\Rightarrow h=\frac{20}{3}$m

$\therefore$ volume $=[15\times 12\times \frac{20}{3}]=1200m^3$