Question

The length of a room is three times its breadth and its
volume is 240mcube
. The cost of plastering its four walls
at Rs. 50 per square meter is Rs. 8000, find the height
of the room.
(Ans: 5 m)
​

Answer 1

Resposta:

5m

Explicação passo-a-passo:

length = x

breadth = 3x

heigtht = y

Volume = x.3x.y=240

x²y=240/3

x²y=80 (*)

And....

8000/50=160 m² for 4 walls

and the area is xy+3xy+xy+3xy=8xy

Then, 8xy=160

xy=160/8

xy=20 m²

Using that x²y=80

xxy=80

x.20=80

x=80/20

x=4 m

But, xy=20 and x=4.

4y=20

y=20/4

y=5 m

I invite you to visit

https://www.youtube.com/user/jessewbasilio