The length and bredth of a hall are in the ratio `4:3` and its height is `5. 5m e t r e sdot` The cost of decorating its walls (including doors and windows) at `R s .6.60p e rs q u a r em e t r e` is `R s .5082.` Find the length and breadth of the room.

Explanation

Let the length, breadth and height be '`4x,3x and 5.5 metres' `respectively.
`Then Lateral 'Surface Area ×6.60=5082'`
⇒ `'2(4x+3x)×5.5×6.60=5082'`
⇒` '14x×5.5×6.60=5082'`
⇒ `'x= 5082/(5.5×6.60×14)=10'`
Hence the length and breadth of the room are `'40m'` and `'30m' `respectively