Given Circumference of a circular base of a cylinder = 44 cm

We know that Circumference of a circle =  $$\begin{gathered} 2 ?r = 44 \\ ? r = 22 ? \end{gathered}$$

Now given the height of a cylinder h = 15 cm

Volume of a cylinder V = ?r 2 h = ? 22 ? 2 15 = 22 x 22 x 15 3 . 14 = 2311 cm 3 .

Given height of the conical tent = 3 m

Diameter = 10 => Radius = D/2 = 10/2 = 5 m 

Now, as the tent is in the conical form

Volume of the conical tent =  ? r 2 h 3 

=> (22 x 5 x 5 x 3) / (7 x 3) 

= 22 x 25/7 

= 78.54 cu.m 

Given each person requires 3.92 cu.m of air 

=> Number of persons can be seated in the tent = 78.54/3.92 = 20.03 =~ 20

Volume of the wall = (2400 x 800 x 60)  cu.cm  

Volume of bricks   = 90% of the volume of the wall 

= [(90/100) x 2400 x 800 x 60] cu.cm  

Volume of 1 brick = (24 x 12 x 8)  cu.cm 

Number of bricks = [(90/100) x (2400 x 800 x 60) ]/ (24 x 12 x 8) = 45000

4/3 ? x 10 x 10 x 10 = 8 x 4/3 ? x r x r x r
r = 5
4? x 5 x 5 = 100?

volume =  a 3 = 729;

=> a = 9

surface area= 6 a 2 =  (6 x 9 x 9) = 486 sq.cm

Let the radii of the smaller and the larger circles be 's' m and 'l' m respectively.  

  2 ?s = 264 and  2 ?l = 352  

 s =  264 2 ? and l =  352 2 ?   

Difference between the areas = ? l 2 - ? s 2   

  =  ? 176 2 ? 2 - 132 2 ? 2 

  = 1762 ? - 1322 ?  

  = (176 - 132)(176 + 132) /  ?  

  = (44 x 308) / (22/7) = 4312 sq.m

Volume of block=(6 x 9 x 12) cu.cm = 648 cu.cm 

Side of largest cube = H.C.F of 6,9,12 = 3cm 

Volume of the cube=(3 x 3 x 3)=27cu.cm 

Number of cubes=(648/27)=24

Volume of the large cube = 3 3 + 4 3 + 5 3 = 216 cu.cm. 

Let the edge of the large cube be a. 

So, a 3= 216 

=>a = 6 cm. 

Required ratio = 6 3 2 + 4 2 + 5 2 6 6 2 = 25 18

 Surface area = [2 (16 x 14 + 14 x 7 + 16 x 7)] sq.cm

= (2 x 434)sq.cm  = 868 sq.cm