The length of a room is two times its breadth and three times its height . if the cost of white wash on the 4 wall at Rs. 50 per m² is Rs. 7200, find the cost of carpeting its floor at Rs. 325 per m²​

Sagot :

Answer:

Step-by-step explanation:

let the height of the room(h) = x

Length(l) = 3*x = 3x

length = 2 * breadth

breadth(b) = length /2 = 3x/2

Cost of whitewashing the 4  walls = ₹ 7200

Area of 4 walls = 7200 ÷ 50 = 144 m²   ------(I)

Area of walls = 2lh + 2bh

                      = 2*3x*x + 2  *[tex]\frac{3x}{2}[/tex] * x

                       = 6x² + 3x²

                        = 9x²

9x² = 144    {From (I)}

x²  = 144/9

x²  = 16

x = [tex]\sqrt{16}=\sqrt{4*4}[/tex]

x = 4 m

height = 4 m

length = 3*4 = 12m

Breadth = [tex]\frac{3}{2}*4=3*2=6 \ m[/tex]

Area of floor = l*b

                    = 12 * 6

                    = 72 m²

Cost of carpeting the floor = 72 * 325 = ₹ 23400